Microscopic Dentistry
A Practical
A Practical
Carl Zeiss
Dr. Tony Druttman
Dr. Greg Finn
Dr. José Aranguren Cangas
Dr. Kristina Badalyan
Slaven Sestic
Dr. Rino Burkhardt
Dr. Annett Burzlaff
Dr. Maciej Goczewski
Dr. Manor Haas
Oscar Freiherr von Stetten
Dr. Bijan Vahedi
Dr. Maxim Stosek
Dr. Claudia Cia Worschech
Dr. Tony Druttman
Dear Reader,
Enhancing the visualization of medical
The authors have succeeded in providing a most
professionals is a core focal point for us at the
valuable guide to using the surgical microscope in a
Medical Technology Business of ZEISS. We strive
range of dental applications. The articles were written
to help our users across a broad range of medical
with the idea in mind that they shall enable a step-by-
disciplines see more. Seeing more can help
step implementation that unlocks the full potential of
clinicians to generate better outcomes, master even
surgical microscopy in your daily practice:
highly complex cases, to gain greater enjoyment
and satisfaction from their work and finally - but
How can the surgical microscope support an
most importantly - improve patients’ lives.
ergonomically correct, upright working position which
is health promoting for the dentist over the long term?
Since its inception in 1921, surgical microscopy has
been crucial for the advancement of several surgical
How can the surgical microscope broaden your clinical
fields, such as brain tumour surgery, vascular
scope and increase your efficiency - as key to the
neurosurgery, cataract or retinal surgery.
realization of a return on your investments?
As Pioneer in Surgical Microscopes, we have
constantly pushed the boundaries of visualization.
How can the use of the surgical microscope add crucial
Today, a large number of the mentioned surgical
benefit to specific procedural steps in every major
procedures would not be conceivable without the
dental application?
use of a surgical microscope.
How can documentation with the surgical microscope
In dental visualization we are at an earlier stage of
increase patients’ involvement in the treatment and
this journey. Even though the surgical microscope
demonstrate your skills?
has become the standard of care in endodontics,
today only a single-digit percentage of all dentists
I am confident that implementing some of the precious
worldwide enjoy the benefits of working with
insights of this book in your daily practice will change
this tool. We firmly believe that this will change
your professional life for the better.
as the surgical microscope will pave the way to
accelerated medical progress in many applications
in dentistry by giving the clinician a greater degree
of control in a range of delicate procedural steps.
In endodontics, the surgical microscope is already
an integral part of the postgraduate curriculum.
For other dental applications, we are not there
yet. Therefore many dentists are seeking guidance
on how to integrate microscopy into their daily
Dr. Christian Schwedes
practice, beyond endodontics. To help fill this gap,
Director Business Sector Dental & Office,
we asked leading clinical specialists in different
Carl Zeiss Meditec AG
disciplines of micro-dentistry to contribute to this
Table of contents
OPMI in Endodontics
OPMI in Periodontology
and Implantology
OPMI in Restorative
and Prosthodontics
Practice Management
25 Why use a surgical microscope?
26 Benefits
27 How the OPMI differs from medical loupes and the
intra-oral camera
of ergonomics
105 Do we need an OPMI
in periodontal and implant
135 Why use the surgical microscope in restorative and
prosthodontic dentistry?
181 Why?
106 What are the advantages
and disadvantages of
the use of an OPMI
in periodontology and
136 Prevention and diagnosis
110 What does the
“microsurgical concept”
consist of?
142 Fractured line – “cracks”
122 Which are the first steps to
getting used to working with
the OPMI?
150 Matrix adaptation
28 The human eye – how it
works and why it is limited
29 Stereoscopy
The components of
Objective lens
Magnification changer
Zoom system
Binocular tube
Set-up OPMI – Quick Guide
Correction for chromatic aberration
42 High transmission of light
Depth of field
44 Field of view
45 How to calculate
end magnification
46 Ergonomics and workflow
47 Looking around the corner –
MORA interface and angled
Light sources
49 Filters and pinhole diaphragm
58 Minimizing overloads
60 Position of dentist
61 Operator range of 9-12 o’clock
working positions
62 Position of the patient
64 OPMI position
66 Functional design
67 OPMI assistance
74 Magnification in endodontics
Working magnification
75 Uses of the OPMI in endodontics
76 Microendodontic instruments
77 Ultrasonics
Ultrasonics tips
Uses of ultrasonics in endodontics
78 Mirrors
Micro instruments Files with a handle
Stropko syringe
Examination of the external surface of the tooth
Identification of the floor
of the pulp chamber
Removal of coronal restorations
Preservation of tooth structure
Assessement of canal cleanliness
after preparation
Identification of internal cracks
Canal location
Calcified canals
Evaluation and management
of perforations
Obturation of the canal
Non-surgical retreatment
Uses of the OPMI
in non-surgical retreatment:
Apical plug with MTA
File evaluation
94 Endodontic root-end surgery
126 How can you acquire
expertise in periodontal
and peri-implant
186 Practical advice
137 Bacterial plaque
148 Preparation control
The benefits of the OPMI
extend far beyond
the obvious and well-proven
clinical benefits.
192 Integration into
clinical practice
193 The OPMI
as a communication tool
Dento-legal aspects
194 Marketing
the OPMI
195 Health benefits to the dentist
153 Rubber dam applications in
anterior and posterior areas
196 Financials of the OPMI
154 Cervical lesions
156 Finishing and polishing
128 Which are the common
errors in the use of the
OPMI in surgical practice?
160 Possibilities for analyzing
the surgical field at different
164 Replacements – avoiding wear
166 The Tunnel preparation technique
168 Indirect restorations
Excellence in operative
and prosthetic dentistry with
regard to communication
with patients
50 Free floating system – balanced system and
magnetic brakes
OPMI and Varioskop are registered
trademarks of Carl Zeiss
The moment you see a hidden detail
reveal a visible success.
This is the moment we work for.
Key benefit 1 // Magnification with OPMI*
You can only treat what you can see…
*OPMI – Operation Microscope
Key benefit 1 // Magnification with OPMI
…or you see more and treat more
Key benefit 2 // Ergonomics
8 hours of spine strain…
Key benefit 2 // Ergonomics
…or 8 hours of working in comfort
Key benefit 3 // Visualization and Documentation
A picture is worth a thousand words…
Key benefit 3 // Visualization and documentation
…for better communication
Author: Dr. Annett Burzlaff
25 Why use a surgical microscope?
26 Benefits
27 How the OPMI differs from medical loupes and intra-oral camera
28 The human eye – how it
works and why it is limited
29 Stereoscopy
The components of
Objective lens
Magnification changer
Zoom system
Binocular tube
Set-up OPMI – Quick Guide
Correction for chromatic aberration
42 High transmission of light
Depth of field
44 Field of view
45 How to calculate
end magnification
46 Ergonomics and workflow
47 Looking around the corner –
MORA interface and angled
Light sources
49 Filters and pinhole diaphragm
50 Free floating system – balanced system and
magnetic brakes
1 The OPMI
Why use an OPMI?
Can you still remember the first time you looked through a
Beginning in 1990, many innovative dentists from numerous
microscope or magnifying glass? Perhaps the first thing you
countries pressed for the use of OPMIs in dentistry: this
saw was a daisy which you thought you knew well, but which
drive towards microdentistry was led by Dr. Syngcuk Kim
then under the OPMI opened up a new world for you. We
(Philadelphia, Pennsylvania) and Dr. Clifford Ruddle (Santa
are not only drawn into the microcosm by our curiosity, but
Barbara, California) in the USA, as well as Dr. Peter Velvart
we also benefit from the insight we can gain into intricate
(Zurich, Switzerland) in Europe, among others. While
details and structures. Microscopy is an integral part of many
endodontics is the main discipline in which OPMIs are
surgical disciplines nowadays. Doctors first used the surgical
used in dentistry, other disciplines such as periodontology,
microscope for microsurgical operations in the ENT area in
implantology or restorative dentistry are adopting the use
1921. Ophthalmologists then attached lighting technology to
of magnification technology. The dentist benefits from
the surgical microscope and used it to perform eye operations.
several advantages of OPMIs, regardless of the discipline.
In the mid-1960s, neurosurgeons recognized the advantages
Magnification enhances the visual acuity and supports more
of using OPMIs for operations. Neurosurgery is today no
precise treatment. However, no light means no information.
longer imaginable without documentation and navigation
OPMIs are therefore designed in such a way that they combine
systems. The OPMI had been undergoing development for
the magnifying lens and the light source. No matter whether
around 60 years before finding its way into the world of
they are working with low or high magnification, the dentists
benefit from shadow-free, direct light. It is natural for us to
orientate ourselves visually in our surroundings. That is how
we judge distances and perceive size and space. We are able
to do this thanks to stereoscopic vision. An OPMI provides the
conditions required for stereoscopic vision and therefore for
depth orientation. This, in turn, enables the safe, precise use
of instruments and improves ergonomics. Relaxed eye muscles
and being able to sit upright during treatment prevent fatigue
and posture impairments.
1 The OPMI
3.5 X
5.1 X
8.5 X
21.25 X
13.6 X
How the OPMI differs from medical
loupes and the intra-oral camera
When working with instruments on a
A correctly configured OPMI can prevent
patient, a certain distance is required
symptoms of fatigue. On the following
In dentistry, the first introduction
enables the dentist to switch between
Intra-oral cameras also provide
between the object, i.e. the tooth in
pages you will find detailed information
into the world of magnification is
overview to detailed view in a matter
magnified images, but they are only
the oral cavity, and the front lens of
about the components of an OPMI,
generally a medical loupe.
of seconds. The working distance of a
two-dimensional and do not provide
the OPMI. This is what is referred to
what makes a good image and how to
A medical loupe fulfills some of the
medical loupe is fixed. Since a medical
any depth information. When looking
as the working distance. In dentistry,
best configure the microscope.
aforementioned requirements and
loupe is worn on the dentist’s head, it
through the OPMI, the dentist has
the working distance with an OPMI is
benefits, but compared to an OPMI
follows every movement of the wearer.
three-dimensional vision which is
usually between 200 and 300 mm to
is somewhat limited in its options.
For the duration of the movement, the
important for orientation and perception
ensure that enough space is provided
Medical loupes are available with a
field of view is blurred to a greater or
of spatial dimensions. This is necessary,
to handle the instruments over the
fixed magnification between 2 - 5
lesser extent. The dentist has to find the
for example, to correctly position the
patient. The correct working distance
times. If the dentist wishes to have a
correct working distance to enjoy a fully
dental instruments. In addition, when
depends on the height of the dentist.
different magnification, this requires
focused image again. The OPMI on the
using the intra-oral camera the dentist
The taller the dentist, the longer the
using a different pair of loupes. The
other hand, is mounted on a stand, is
has to interrupt the workflows to record
working distance. Using the correct
magnification factor of an OPMI is
moved into position by the dentist and
images. Video recording of treatment
individual working distance on an OPMI
variable between approximately 1.5 -
then remains stable. Special optics allow
has to be done by a third party.
is crucial for a correct working posture.
30 times and can be altered by using
the working distance to be changed
Conversely with an integrated camera
Using an OPMI supports the ergonomics
the magnification changer or zoom
to ensure a comfortable working
or with still or video cameras attached
of the dentist as the microscope can
system, depending on the model of
posture of the dentist. The higher the
to the OPMI, images or video recordings
more or less look “around the corner”.
OPMI. While an overview of the mouth
magnification of loupes, the heavier
of exceptional quality can be obtained
Therefore, the dentist can sit upright
can be seen at lower magnifications,
they become and therefore potentially
while treatment is being carried out.
and benefits from good ergonomics.
detailed structures can be viewed
more uncomfortable. Modern loupes
better using the higher magnification
also have a battery operated headlight
of an OPMI, e.g. to locate a root canal,
which needs to be recharged
or to find additional root canals. This
1 The OPMI
The human eye – how it works and why it is limited
Optical axis
Large working distance
Large angle of view
Small angle of view
Figure 1.1: The focused object is on the optical
axis. The farther the object is removed from the
eye, the smaller the angle at which it is projected
on the retina. Finer details can be recognized only
if the object is closer to the eye and thus the angle
to the retina is greater
The human eye is a flexible optical
depicted on the retina with a small angle
near objects. The ability to see detailed
The fact that we have two eyes that
an instrument is in front of, next to or
system that can adapt to various
of view. To be able to see fine details,
structures also begins to deteriorate. An
are adjacent to one another forms the
behind an anatomical structure. In order
requirements. It can produce an image
we have to bring the object closer to
OPMI overcomes these natural limitations.
basis of stereoscopic vision. The left and
to enable this orientation, OPMIs are
of objects at a great distance, but we
the eye. As a result, the angle of view
On the one hand, it magnifies detailed
right eyes perceive a particular object
designed as stereomicroscopes. This
can also read a text that is only
increases and we can break down the
structures, and the fine structures can
from two different angles (parallax).
enables the left and right eyes to view
30 cm away. The eye adjusts to various
individual structures (Figure 1.1). This is
then be distinguished. On the other hand,
The brain then puts these two slightly
an object from slightly different angles.
distances. In order to focus objects at
why a dentist has to bend down over the
the eye can adjust almost to infinity when
different sets of visual information
We can then retain three-dimensional
various distances, a system of muscles
patient’s oral cavity in order to be able to
looking through an OPMI. This relaxes the
together to form a 3D image. This
vision and this depth perception when
generates the required refractive power
see details at a distance of approximately
ciliary muscles and fatigue symptoms are
allows us to see the third dimension, to
looking through the OPMI.
for the lenses of the eyes. If we look
30 cm. The easiest type of magnification
estimate distance, size and position and
at a landscape, the ciliary muscle is
is therefore to bring an object closer to
to orientate ourselves. We also require
relaxed and the lens is flat. However,
the eye. However, the eye’s abilities are
three-dimensional image information
if we read text, the ciliary muscles
limited. A baby can clearly see objects
when looking at a treatment area. Only
contract, causing the lens to become
that are 7 cm away, a 30 year-old person
with three-dimensional vision are we
convex. The refractive power is thus
at 30 cm. On reaching the age of 40,
able to determine whether the tip of
increased and we can clearly recognize
most people become presbyopic and
small letters. Extended contraction of
the distance between the object and
the ciliary muscle can cause fatigue. In
the eye becomes increasingly bigger.
order to relax the eyes, we look to a
The eye’s ability to accommodate to
more distant scene. If we look at a small
short distances deteriorates, meaning
object from a greater distance, it is
that we can no longer focus as well on
1 The OPMI
The components of an OPMI
Before going into greater detail about the individual
components of an OPMI, let us first look at the
optical paths (Figure 1.2).
Image plane
on the retina
image plane
Tube Head
If the treatment field is in the focal
Objective lens
plane of the objective lens, the objective
The objective lens is the first optical
the focal distance, i.e. the working
component that the image information
distance of the lens, the greater the
crosses on its path from the object to
end magnification (for calculation of
the eye. The lenses vary in their focal
the end magnification, see Section
beam splitter can be inserted. The
distance (= focal length). This influences
4.5) and the greater the resolution.
magnification changer magnifies or
the working distance (i.e. the distance
The lens should be equipped with a
minimizes the image by a given factor.
between the object in the treatment
fine-focus knob. That means that even
The binocular tube head is placed on
field and the surface of the lens), the
at high magnification levels, images
lens creates an image at infinity. Behind
the main objective lens the optical
paths are parallel. Different components
like the magnification changer or the
OPMI body with
magnfication changer
magnification and the resolution. These
can be precisely focused over a short
eyepieces for the left and right eyes.
three criteria influence one another.
distance (e.g. when viewing root canals
The two optical paths provide slightly
The most common working distances
in great detail). To change the working
different viewing angles, which creates
are 200, 250 and 300 mm. The focal
distance, the lens must be unscrewed
distance of e.g. f = 250 mm is engraved
and replaced with an lens with a
from the object. The left and right optical paths in
on the lens mount. This roughly equates
different focal distance. However, this is
is referred to as the stereo base. The
the OPMI view different angles of the object and
to the working distance of the lens.
impractical in practice and interrupts the
stereo base is essential for producing a
thus create the impression of a three-dimensional
In order to view the image clearly, the
workflow. A varioscope is useful in this
image depending on the selected position. The
OPMI lens ( e.g. f = 250 mm) must have
event and offers much more flexibility
tube creates an intermediate image
tube lens of the binocular tube head creates an
a working distance of approximately
as it can change the working distance
which is magnified by the eyepiece and
intermediate image of the object, which is projec-
250 mm to the object. The object is
the OPMI body and contains the two
the stereoscopic image impression. The
distance between the two optical paths
three-dimensional image. The binocular
projected onto the exit pupils. The lens
of the eye then receives the image and
focuses it on the retina.
Figure 1.2: The lens collects the image information
image. The magnification changer magnifies the
ted into the eye, magnified with the eyepiece. The
the right way. The tube head allows adjustment of
The OPMI can be raised or lowered
the pupil distance, so that the pupils of the viewer
to focus the object, provided the lens
match the OPMI‘s exit pupils
then within the focal point of the lens.
prisms in the binocular tube head rotate the image
Object plane
has been set to a distance of e.g.
250 mm from the object. The shorter
1 The OPMI
Internal displacement
of the lens system
Figure 1.4: The working distance can be changed
according to the internal displacement of the
varioscope’s second lens system. There are motorized varioscopes which focus on the image at the
press of a button. Therefore, the dentist can focus
Large working
without changing his or her own seated position.
The height of the OPMI can be set in a range from
Small working
200 to 415 mm, e.g. above the patient‘s oral cavity.
This allows the dentist to adjust the OPMI to suit his
or her individual ergonomic needs
Object plane
Figure 1.3: Using Varioskop 100 of OPMI pico the
dentist can focus continuously, for example, from
the incisors to the molars in the patient‘s oral cavity
without changing the position of the OPMI. The
height of OPMI pico can be set in a range from 200
to 300 mm above the patient‘s oral cavity allowing
Unlike an objective lens with fixed focal
adaptation to the personal ergonomic needs of the
length, a varioscope has a variable
focal length. Therefore, it can be set to
a range of working distances to meet
different application and ergonomic
requirements. The focal range of a
up and down results in much more
motorized varioscope of OPMI PROergo,
Figures 1.5a, 1.5b: OPMI PROergo
varioscope can be varied from 200 to
precise focusing and speeds up the
it can be controlled by pressing a
comes with a motorized varioscope.
300 mm or even from 200 to 415 mm
workflow. How is this possible? The lens
button on the handgrip (Figure. 1.5).
depending on the OPMI. This ensures
system of a varioscope is composed of
This makes the workflow more efficient
a wide range of working distances for
two lens groups. To focus at a selected
and contributes significantly to the
a comfortable working position, even
working distance, the upper lens group
ergonomics of the OPMI. Automatic
for hours at a time. Unlike an OPMI
is repositioned along the optical axis
focus is even more convenient.
with a fixed focal length lens, it is not
(Figure 1.4). The adjustment of the
By pressing a single button, the ZEISS
necessary to raise or lower an OPMI
focal plane within the working distance
SpeedFocus system of the OPMI
with a varioscope to focus it within its
range can be performed manually
PROergo focuses the OPMI in a matter
focal range. For example, it is possible
(S100 / OPMI pico with Varioskop 100)
of seconds by analyzing live images
to focus by turning the focus knob of
or motorized (S7 / OPMI PROergo).
recorded by a camera.
the varioscope from the incisors to
When using a manual Varioskop 100
the molars in the patient’s oral cavity
on OPMI pico, it can be controlled
without moving the OPMI. Using the
by manually turning the knob on the
varioscope instead of moving the OPMI
varioscope (Figure 1.3). When using a
The dentist can vary the working
distance over a range of
200 – 415 mm by using the
control button of the handgrip
1 The OPMI
Figure 1.6: A five-step magnification changer is
composed of a turret with two telescopes and one
position without a lens. Depending on the position
of the magnification changer in the optical path,
there are different magnification factors.
The factor in the lens-free position is 1.
Zoom system
Magnification changer
During treatment it is important
empty position without optics that
The advantage of step magnification
Zoom systems allow the magnification
A zoom system shows its full
that the magnification factor can be
provides a magnification factor of 1.
changers is their compact construction
of the overall system to be set as
potential when motorized as in
altered to gain an overview at lower
Therefore, a total of 5 magnification
with low technical complexity, yet
required by the treatment. The dentist
S7 / OPMI PROergo:
magnifications and to view in more
factors are available. Usually the
high optical quality and efficiency. The
can continuously change between
• stepless zoom
detail at higher magnifications. There
magnification factors are 0.4, 0.6,
limitation is that magnification can
overview and a detailed view. As with
• faster adjustment of magnification
are two technical solutions for this
1.0, 1.6, 2.5. (Please note that these
only be selected in steps, and the view
the magnification changer, the zoom
• control via multi-functional handgrip
purpose: the magnification changer
numbers are not the end magnifications.
of the treatment area is blocked while
ratio (1:6) can be calculated by dividing
• control via foot switch. If the dentist
(= Galilean changer) and the stepless
To calculate the end magnification,
the turret is being turned. Turning
the highest magnification factor (2.4) by
uses a foot switch, he or she can
zoom system. The majority of OPMIs are
further optical parameters must be
the magnification factor must be
the smallest (0.4). The zoom system is
adjust the zoom factor without having
fitted with a magnification changer. The
considered, as described in Section 4.5).
performed manually. Zoom systems are
composed of several optical elements,
to take their hands off the instrument.
most common magnification changer
The ratio between the largest and the
considerably more convenient.
of which two are adjustable. By altering
has 5 steps. The optical principle is
smallest magnification factor gives the
the position of the two adjustable
checked: in combination with an
an astronomical telescope, called the
extension range of the magnification
elements over a precisely calculated
internal video camera, the end
Galilean telescope after its inventor.
changer: 2.5 / 0.4 = 6.25
curve, the various magnification factors
magnification or a scale bar can be
The magnification ratio is 1:6.25.
can be achieved smoothly along the
• the magnification level can be
displayed on the monitor.
• For the purposes of documentation,
The magnification changer is composed
magnification range. In order to achieve
of a turret with two telescope systems
the stereoscopic effect, there are two
the image section can be optimally
of different magnification factors
parallel optical paths in the zoom system
adjusted to the size of the camera
(Figure 1.6). By turning the turret the
that must behave absolutely identical
sensor, so that a tooth, for example,
telescopic systems can be viewed in
with regard to their optics and precision.
can be displayed to fill the whole
either direction to achieve different
photo or monitor.
magnification factors. There is a total
of four magnification factors plus one
1 The OPMI
Figure 1.7a: For more user comfort, the distance to the
Figure 1.7b: The foldable tube f170 / f260 head accommodates easily to the various ergonomics of
surgical field can be adjusted as needed with the
different operators. Both dentists can work with the same working distance as the different eye levels of
multi-link design of the foldable tube f170/f260 head.
the dentists are compensated for by the adjustable foldable tube f170 / f260 head. The foldable tube head
can be mounted to OPMI pico or OPMI PROergo
Binocular tube
OPMIs are used in an almost
long reach and multilink design this
Just like a magnifying glass, the two
ability is limited and the dentist needs
perpendicular position above the
tube head accommodates different
eyepieces magnify the intermediate
to be able to see normally when not
patient in dentistry. In order to provide
ergonomics of different operators or
image produced in the tube.
looking through the OPMI. Certain eye
the dentist with a comfortable and
different positions of the patient.
problems, e.g. astigmatism, cannot
The magnification factor (10x or 12.5x)
be corrected by the eyepiece. If the
Figure 1.8: The blue circle corresponds to the
inclinable or foldable tube head is
The tube head also uses the stereoscopic
is labeled on the eyepieces. Thus, the
refractive error of the eye is corrected
field of view of a 10x eyepiece and the red
mounted to the OPMI body and directs
principle of the left and right optical
eyepieces have an effect on the end
by prescription lenses, the dioptric
circle corresponds to the field of view of a
the optical path to the eyes of the
path for a three dimensional image.
magnification. Anyone requiring as high
correction of the eyepiece should be
dentist. A 45° inclined tube head is
The binocular tube head contains a lens
a magnification as possible (e.g. for
set to 0. The dentist’s eyes must be at
fixed at an angle of 45° and offers
and has a defined focal distance
endodontics) will choose eyepieces with
a certain distance to the eyepieces so
that, conversely, the maximum final magnification
limited ergonomics. A inclinable tube
(e.g. f=170 mm as shown on the tube
12.5x magnification. Eyepieces with 10x
that they are in the exit pupils of the
is higher when using a 12.5x eyepiece
head (0-180°) allows the dentist to
head). Prisms inside the tube head
magnification do, however, provide a
eyepieces and can see the entire field of
alter the angle of the eyepiece holders
create an upright, accurate image. The
considerably larger field of view, and can
view. Eyecups or distancing rings should
by 180°. That means that the viewing
eyepieces in the binocular tube head are
therefore provide a better overview of
be extended when using the OPMI
angle of the tube can be adjusted to the
the interface between the OPMI and the
the entire treatment area (Figure 1.8).
without glasses. Dentists who wear
position of the OPMI in such a way that
dentist’s eyes. The distance between the
the dentist’s head can remain upright
pupils varies from person to person and
Eyepieces are fitted with a ring for
rings as the glasses already function
and the dentist does not have to lean
ranges from 54 to 76 mm. It is essential
dioptric adjustment. This means that
as a spacer. Figure 1.9 (next page)
backwards or forwards - an important
to set the correct individual distance,
dentists with perfect or impaired vision
shows the individual steps for personal
requirement for relaxed, ergonomic
otherwise the eyes quickly become
can use the OPMI. Ametropia can be
configuration of the OPMI.
work. Even more flexible and adaptable
fatigued and 3D perception is lost. The
corrected to a limited extent. Dentists
to different body heights and working
setting of the eyepieces is described in
with impaired vision should wear their
postures of the dentist is the foldable
Section 3.6.
glasses or contact lenses when using the
ergonomic view into the OPMI, a
tube head (Figure 1.7). Thanks to its
12.5x eyepiece. An eyepiece with 10x magnification
provides about 20 percent more field of view than
an eyepiece with a factor of 12.5x. This means
glasses should retract the distancing
OPMI, because the OPMI’s corrective
1 The OPMI
Set-up of OPMI
Quick Guide
Initial setting
Adjusting the eyepieces
Set the OPMI to the lowest
Dioptre correction
magnification. Select the
Adjust the eyecups in such a way that
Set the diopter setting ring on the OPMI
magnification factor 0.4 on the
the entire field of view can be seen.
to 0 dioptres.
Figure 1.12a Viewing without eyeglasses: screw out
Figure 1.12b Viewing without eyeglasses: set dioptre
the eyecups until 2-3 silver rings are visible
correction according to your correction value of the
magnification changer (Figure 1.9).
Focus: To focus the image move
the OPMI up and down to achieve
the correct working distance in
accordance with the focal length of
the objective lens (e.g. 250 mm).
Figure 1.9 magnification changer
eye (e.g. -1)
Adjusting the interpupillary
Start from the widest position of the
eyepieces and use knob of the tube
head to adjust the distance of the eyepieces to your interpupillary distance
(Figure1.11) so that the two eyepiece
Figure 1.12c Viewing with eyeglasses: screw in
Figure 1.12d Viewing with eyeglasses: set dioptre
the eyecups all the way (no silver ring visible)
setting ring on the OPMI to 0 dioptres
images merge into one (Fig 1.10a - c)
Adjusting magnification
and focus
Figure 1.10a Widest position
Figure 1.10b Adjusting the distance
Figure 1.10c Correct distance
Select the maximum magnification
and focus: focus on the object by
lifting and lowering the OPMI and/
or using the focusing dial (Fig 1.13).
Select the magnification required.
The focal plane is retained.
Figure 1.11 Interpupillary distance in mm at
Figure 1.13 Adjusting the focus dial
1 The OPMI
In order to see fine detail on the treatment field, good image
quality is essential. But what exactly is good image quality?
The most important criteria are discussed here in more detail.
Longitudinal chromatic
aberration, red-blue
Figure 1.14: The stereo co-observation tube
Without correction
is coupled with the OPMI via a beam splitter
and can be put in the required position using
pivot joints.
Correction of chromatic aberration
Co-observation means that a second
operator can look down the binocular
the stereo base is smaller. The
If you hold a prism in the sunlight, the
person (e.g. assistant) or even more
tube and the co-observer, e.g. the
stereoscopic co-observer tube can
white light is split up into its separate
persons (e.g. students, colleagues) can
assistant, or assistant surgeon can look
be tilted and turned, thus providing
colors - we see the colors of the
follow the treatment under the OPMI.
down the co-observation tube. The co-
convenient viewing. An image
spectrum. This happens because the
Usually a camera is used to show the
observation tube can be connected via
rotation prism places the image
shorter-wave blue light is refracted more
live image on a monitor. The advantage
an optical splitter between the OPMI
in the desired position. The stereo
strongly than the longer-wave red light.
of a camera-based co-observation is
body and the binocular tube. The optical
co-observation tube adds weight
A similar phenomenon occurs when
that one or more persons can follow
splitter splits the image information from
to the OPMI. Before mounting a
light passes through a lens. The focal
the treatment without directly looking
one of the observation optical paths
co-observation tube to the OPMI it
distance of the blue light is shorter than
through the OPMI. At the same time it is
and redirects it into the co-observation
is important to check whether the
the focal distance of the red light. The
possible to record videos or to make still
tube. The co-observer therefore has the
suspension system of the OPMI can
focal point of the blue light is therefore
images for documentation.
same view of the treatment area as the
carry the additional weight.
closer to the lens than that of the red
An integrated camera is built into the
2. The monocular co-observation tube.
light. As a consequence, the back focal
This offers the co-observer a view
point becomes blurred, which leads to
Apochromatic correction
Longitudinal chromatic aberration,
red-blue (within the resolution limit)
blue color spectrum
green color spectrum
red color spectrum
OPMI body and does not add much
There are two kinds of co-observa-
with only one eye. This can be used,
poor contrast, chromatic aberration and
weight to the system, which makes
tion tubes:
for example, for workshop OPMIs if
low resolution (Figure 1.15). Correction
the handling of the OPMI easy. On the
1. The stereoscopic co-observation tube.
the teacher would like to co-observe
of these chromatic effects is essential
other hand, the video image on the
With this tube, the co-observer looks
the student’s work under the OPMI.
for brilliant image quality. OPMIs that
screen is two-dimensional and has no
into a binocular tube with both
contain apochromatically corrected
depth. To achieve 3D perception for
eyes and sees a stereo image
lens systems stand out because of their
the co-observer it is possible to mount
(Figure 1.14), although the
increased resolution and high contrast,
a co-observation tube on the OPMI. A
stereoscopic effect is slightly reduced
even at the periphery of the viewing
co-observation tube enables a second
for the co-observer compared to
area. No chromatic aberrations can be
colors. After apochromatic correction, the different colour components of light are nearly
person to look into the OPMI. Thus, the
that of the main observer because
focused at a single point. The result is brilliant image quality without visible chromatic aberration.
Figure 1.15: When white light passes through a lens, it is broken into its spectral components. Blue light is
refracted more than red and thus focuses closer to the lens. Therefore, there is no single focal point for all
1 The OPMI
aperture closed
aperture open
aperture closed
Figure 1.16: The depth of field is the area above
and below the focal plane, which appears in
focus to the viewer. The smaller the selected
magnification and the larger the working distance,
High transmission of light
Depth of field
When light crosses the optical elements
When focusing an object in the OPMI,
of the OPMI, it can cause reflections on
we focus on a particular focal plane.
the surfaces of the lenses. These reduce
We can also see an area above and
the clarity of the image and can lead
below the focused area with equal
to a loss of light. Coating all lenses and
clarity. These areas are referred to as
2. Working distance: the greater the
individual basis, which is why OPMI
prisms reduces reflections within the
the depth of field. Needless to say, it is
working distance, the greater the
manufacturers generally do not state
OPMI. Light transmission and image
most comfortable to work with as high
depth of field.
the depth of field. However, depth
contrast are then higher.
a depth of field as possible as this allows
the greater the depth of field becomes. If a doubleiris aperture is included in the light path, you can
better spatial orientation. However,
From the first two of the three
double iris aperture therefore depends
magnification, the greater the depth
parameters stated, depth of field can
on the desired effect with a particular
of field.
indeed be calculated. The biological
application. Usually the double iris is
component does however vary on an
used for high-end photography
1. Magnification: the lower the
close this to increase the depth of field
of field can be increased by inserting
3. Aperture of the objective lens:
a double iris aperture in the optical
depth of field is an optical property that
the aperture determines at what
path. If it is closed, the depth of field
is influenced by several parameters.
angle light beams are still captured
increases, especially in the medium
by the lens. The lower the angular
magnification range (Figure 1.16).
aperture of the lens, the greater the
The disadvantage is that light is lost
depth of field.
in this process and therefore the light
intensity has to be increased. Closing
4. Adaptability of the observer: this
the aperture reduces the resolution,
is where biology comes into play.
meaning that the resolution of very
A younger dentist‘s eyes generally
small structures is reduced. If the double
adapt better, and can therefore make
iris aperture is opened, the image
out depth of field over a longer area.
becomes brighter and the resolution
With increasing age, the adaptability
of fine details increases. The use of a
of the eyes decreases, as does the
depth of field.
1 The OPMI
Figure 1.18a OPMI pico with fixed focal length lens
with 250 mm focal length covers a field of view
of 75 mm.
Figure 1.18b OPMI pico with Varioskop 100 covers
Working distance 415 mm, 12.5x eyepiece
a field of view of 95 mm at same magnification.
Working distance 200 mm, 12.5x eyepiece
Zoom factor 0.4
Zoom factor 2.4
Zoom factor 0.4
Zoom factor 2.4
End magnification 1.9x
End magnification 10.9x
End magnification 3x
End magnification 18.2x
Field of view 116 mm (diameter)
Field of view 20 mm (diameter)
Field of view 73 mm (diameter)
Field of view 12 mm (diameter)
(a and b with 10x eyepiece, magnification factor
75 mm
0.4, binocular tube f=170 mm)
95 mm
Figure 1.17: The S7 / OPMI PROergo manufactured
by ZEISS reaches up to a 116 mm field of view at
It can be calculated easily with the following formula:
the lowest magnification, a 12.5x eyepiece, a tube
focal distance of 170 mm and a working distance
of 415 mm. The diameter of the field of view
End magnification =
and magnification depend on the working
Tube focal distance
Lens focal distance
x Magnification changer factor x Eyepiece factor
distance. If the working distance is shortened
(e.g. to 200 mm), then the field of view decreases
and the magnification increases
Field of view
The following applies:
The field of view is the area of the
1. Magnification: the lower the
treatment field that can be seen
magnification, the larger the field of view.
How to calculate end
Example 1:
Example 2:
Focal distance tube: Focal distance tube:
f = 170mm
f = 170mm
through the OPMI. For the purposes
The magnification with which we can
see a structure in the eyepiece is the end
of orientation, it is most convenient to
2. Working distance: the greater the
magnification. It is the end result of the
Focal distance of lens: Focal distance of lens: work with as large a field of view as
working distance, the larger the field of
various optical components of an OPMI.
f = 250 mm
f = 250 mm
The formula for the calculation of the
Magnification changer factor:
Magnification changer factor:
3. Lens system: the size of the fields of
end magnification applies to OPMIs with
2.5 x
view depends on the lens design.
fixed focal distance. This formula cannot
be used for OPMIs with a varioscope
Eyepiece factor:
Eyepiece factor:
because the working distance does not
equate to the focal distance. The best
way to find out the end magnification in
170 x 0.4 x 12.5 = 3.4
170 x 2.5 x 12.5 = 21.25
this case is to ask the manufacturer.
3.4x is the lowest
21.25x is the highest
magnification at a
in this example.
magnification factor of 2.5,
with the other parameters
identical to those in example 1.
1 The OPMI
Ergonomics and workflow
Surgical microscope provides proper ergonomics for the eyes
and for the back. If a dentist works on a patient without
magnification, his or her eyes accommodate to a distance of
about 30 cm and tire easily. However, if he or she looks through
an OPMI, the eyes accommodate almost to infinity, which serves
to prevent fatigue.
An OPMI supports the dentist‘s ergonomic sitting position. Normally,
the dentist leans over the mouth of the patient, which can lead to back
problems. If the dentist works with an OPMI, then he or she sits upright
and looks straight ahead into the eyepieces of the OPMI. Inclinable tubes
allow the viewing angle to be adjusted in line with the working height and
seating position of the dentist.
Figure 1.20: The MORA interface
allows the OPMI to be tilted to the left
or right. The eyepieces retain their horizontal position, so that the dentist has
a straight, ergonomic seating position
when looking into the OPMI.
Looking around the corner – MORA
interface and angled optics
A varioscope contributes significantly to
ergonomics, as it allows you to change
If the OPMI is equipped with a MORA
balance of the OPMI. This is especially
the working distance within a range
interface, the microscope body can be
important when it comes to external
of e.g. 200 – 300 mm or even 200 to
moved to the left or the right by hand
camera attachments.
415 mm without requiring the dentist
without changing the position of the
A MORA interface can be combined
to change his or her working position.
binocular tube head (Figure 1.20). The
with a documentation output port, and
Motorized zoom and focus at the push
dentist‘s head and upper body remain
the camera is thus directly attached
of a button on the handgrip of the
upright and relaxed. The OPMI looks
to the MORA interface. Therefore,
OPMI accelerate the workflow.
“around the corner”. As an alternative
the camera attachment is not moved
to the MORA interface, angled optics
when the OPMI body is swung. Angled
can be used, which also serve to guide
optics, on the other hand, require the
the image to the viewer‘s eyes. An
entire OPMI to be moved, including the
angled optic is usually combined with
external camera. This is less ergonomic.
Figure 1.19a: The Varioskop 100 of S100 / OPMI
Figure 1.19b: The motorized varioscope of
a rotatable dovetail mount. Therefore,
pico allows focussing in the range from 200 - 300
S7 / OPMI PROergo provides a focusing range of
mm by turning the focus knob manually.
200 - 415 mm and can be controlled by
the dentist can swing the OPMI to the
autofocus or by the push of button.
side and bring the tube into a nearly
straight position with a second hand
motion. In contrast to the MORA
interface, this way of working requires
two hand movements instead of one,
thus providing a less efficient workflow.
Another advantage of the MORA
interface over an angled optic consists
of the better weight distribution and
1 The OPMI
Light is the eye‘s information medium. But the light
situation is difficult in the patient‘s oral cavity. Surgery
lamps are good for illuminating the area being treated,
but a root canal or fracture can often be in shadowed
In an OPMI, the light is integrated coaxially via the lens
(Figure 1.21), thus ensuring optimum illumination of
cavities (e.g. root canals).
Figure 1.22a: Halogen
Figure 1.22b: LED
Figure 1.22c: Xenon
Figure 1.21: The light coming from
Figure 1.22a -1.22c: Compared to halogen light
the light guide on the rear side of
source, LED and xenon show light that resembles
the OPMI is reflected by an internal
natural daylight. Xenon light features the highest
mirror through the lens onto the
intensity of all three light sources and enables short
treatment area. The coaxial light
exposure times for sharp image documentation.
provides shadow-free illumination
and illuminates cavities like root
Light sources
Filters and pinhole diaphragm
Xenon light has the advantage that
then the intensity of light at the object
usually specified at 70000 hours (based
In order to prevent premature curing of
This makes sense for two reasons:
its color temperature is similar to that
is reduced to a quarter. With increasing
on average use of the light intensity
composite material, OPMIs are equipped
1. The contrast of the microscopic
of daylight. In other words, it is white
magnification, brightness also decreases
similar to maximum halogen light).
with an orange filter. This can be
image increases, because light is
light. White light gives the viewer
at the viewer‘s eye.
Compared to LED and xenon, halogen
placed in the light path when working
reflected off fewer structures (e.g.
has a lower color temperature and
with composite material. A green filter
instruments) and thus less diffused
natural and also provides true-color
High-end OPMIs like OPMI PROergo
thus appears yellowish to the eye. In
increases the contrast between the
light is produced.
reproduction for documentation (Figure
automatically compensate for this
addition to this, the color temperature
blood-filled and bloodless tissue, thus
1.21). The intensity of xenon lamps is
by adapting the light intensity to the
changes when the intensity is regulated.
making details more visible. OPMI
180 watts for example, and is therefore
selected magnification (e.g. increasing
If the intensity is adjusted to a low
PROergo is equipped with a pinhole
at higher levels of magnification and
higher than that of conventional 100-
it at higher levels of magnification).
setting using a potentiometer, then the
diaphragm in the lighting unit, which
therefore the field of view is brightly
watt halogen lights. Light intensity
The life of a xenon lamp is defined by
spectrum of the halogen lamp becomes
reduces the size of the illuminated
illuminated. The bright light and
is particularly important when the
the manufacturer (e.g. 500 hours).
even more reddish. The life of a halogen
area. This is useful at higher levels
reflective instruments could impair
dentist works with high magnification
The xenon lamp should be replaced
lamp (e.g. 50 hours) is also much shorter
of magnification because the field of
the assistant ’s ability to see properly.
for example on root canals and for
so as not to pose the risk of flare
than that of a xenon lamp or LED.
view is smaller. It is not necessary to
The pinhole diaphragm can be closed
documentation. Especially those dentists
or non-homogeneous illumination.
illuminate a large area. Therefore, the
to the extent that the field of view is
working with SLR cameras depend on a
An alternative to xenon light is LED
diameter of the illuminated area can be
illuminated, but annoying reflections
high level of intensity to keep exposure
light. LED light comes close to a color
reduced using the pinhole diaphragm.
are reduced.
times short and thus minimize the risk
temperature similar to that of daylight.
of camera movement affecting the
The intensity of an LED light source is
image. The larger the working distance
lower compared to xenon. Currently LED
when using an OPMI the further light
lighting cannot yet replace traditional
has to travel. If the working distance is
xenon lighting in terms of intensity. The
doubled (e.g. if a working distance of
big advantage of LED is its considerably
400 mm is selected instead of 200 mm),
longer lifetime. The service life of LED is
the impression that the object looks
2. The dentist increases light intensity
1 The OPMI
Free floating system
Balanced system and magnetic brakes
There are several ways to mount an
While working, it should be easy to
Smudged optical surfaces dramatically
brush. For cleaning of objective lenses
position the OPMI above the patient and
reduce image quality. Image quality is
and eyepieces, it is recommended to
it should require no effort to move it out
impaired by even slight soiling of the
use optical cleaning solutions and a
Movable floor stand
of the way after completing treatment.
optics or by a fingerprint. Spatter on the
microfiber cloth.
Wall mount
The stands are equipped with a balance
lens reduces contrast and sharpness. In
Ceiling mount
system for easy and precise OPMI
order to protect optical surfaces of an
The mechanical surfaces of the OPMI
positioning. Depending on the weight
OPMI from dirt, it is advisable to cover
can be cleaned by wiping with a damp
The choice of suspension system
of the OPMI, the balance system can
the microscope when not in use. During
cloth. Clean off any residue using a
depends on the conditions at hand.
be set, so that the OPMI seems almost
use, the lens can be covered with a
mixture of 50 percent ethyl alcohol and
A floor stand allows you to roll the OPMI
weightless when moving. Magnetic
splash guard. This prevents splashing
50 percent distilled water plus a dash of
from one treatment room to another.
brakes are advantageous because they
of the lens with blood and aqueous
household dishwashing liquid.
Ceiling and wall mounts are firmly
fix the position of the OPMI (S7 / OPMI
solutions and can be easily cleaned.
anchored in place and require no floor
PROergo). If the OPMI has to be moved,
Clean the exterior surfaces of the optical
space. When planning wall and ceiling
then the brakes are released by pushing
components (eyepieces, objective lenses)
mounts, it is essential
a button, the device is repositioned
only when necessary. Do not use any
to test the sturdiness of the wall and
and the brakes are applied again by
aggressive or abrasive agents. Remove
ceiling as well as possible sources
releasing the control buttons. If you
dust from the optical surfaces using a
of vibration (such as elevators, air
change the weight of the OPMI system,
squeeze blower or a clean, grease-free
conditioners, intensive heavy traffic on
for example, by adding or removing
the road). Vibrations can be transferred
an external camera, then you have to
to the stand and affect the image
balance the device again.
Author: Dr. Bijan Vahedi
Dr. Maciej Goczewski
Oscar Freiherr von Stetten
of ergonomics
58 Minimizing overloads
60 Position of dentist
61 Operator range of 9-12 o’clock
working positions
62 Position of the patient
64 OPMI position
66 Functional design
67 OPMI assistance
2 Ergonomics
Definition of ergonomics
Ergonomics is the scientific discipline concerned with
the understanding of interactions between humans
and other elements of a system. Ergonomics is also
the science that applies theory, principle, data and
methods to design in order to optimise human wellbeing and overall system performance.
The word ergonomics comes from the Greek. It stems
from two separate words – ergon, which means work,
and nomos, which means correctness. In short, we can
say that ergonomics means working correctly.
Figure 2.1
2 Ergonomics
Figure 2.3
Figure 2.4
If the settings of the System Operator-
In order to minimize overload, we have
OPMI are not set correct, an advert
to work ergonomically, which means
affect in terms of Back/Neck-Discomforts
that we have to eliminate incorrect
can appear.
posture and alter our technique
accordingly. There are two types of
This phenomenon stems mainly from
muscle overload - static and dynamic.
muscle overload that cannot be
eliminated entirely, but can be reduced
Static overload results from prolonged
to such an extent, that it no longer
periods of work in one position,
causes any discomfort.
immobility and muscle cramp. Dynamic
overload results from frequent repetition
the same movements.
Figure 2.2
2 Ergonomics
Minimizing overload
2.6 a Rotating hips
2.6 b
2.6 c Raised shoulders
2.6 d
2.6 e Rotating torso
2.6 f
2.6 g Tilted neck
2.6 h
The following basic positions should
be used to reduce overload. First, the
dentist should assume an adequate
seated position. Second, the patient
should be placed in the correct position.
Third, the OPMI should be positioned
Figure 2.5
2 Ergonomics
Figure 2.7
Figure 2.8a 9 o´clock position
Position of dentist
Operator range of 9-12 o'clock
Figure 2.8b 12 o´clock position
working positions
Standard dental treatment often results
Avoiding overload for the treating
in tension in the shoulders and neck.
dentist, particularly in the critical
The position of the dentist in relation to
The 12 o'clock position behind the head
This is due to a statically overloaded
shoulder-neck area, requires an
the patient is ideal at a range from 9-12
of the supine patient is the ergonomical
seated position.
adequately supported seated position.
o'clock. However, when using an OPMI,
position for most dental procedures.
the position during most treatments
A chair featuring individually adjustable
moves from the 9 to the 12 o'clock
armrests and support for the lower back
area is recommended as seen in
figure 2.7.
When the dentist sits in this supported
and comfortable position, this reduces
static overload and enables more
precise motor coordination during
2 Ergonomics
Figure 2.9
Figure 2.10a
Figure 2.10b
Figure 2.11a Head rest adjusted for indirect (mirror) view of mandible where
Figure 2.11b Head rest positioned for indirect view of the maxillary teeth with
the mandibular occlusal plane is vertical.
maxillary occlusal plane vertical.
Figure 2.12a
Figure 2.12b
Figure 2.12c
Position of the patient
Once the dentist is seated correctly, the
Most treatments can be performed on
When indirect viewing via a mirror is
In order to obtain a good view of the
patient must be moved into a suitable
the upper jaw when the patient is lying
required and visibility is poor, it is often
treatment field, it is often unnecessary
treatment position.
flat or slightly inclined.
necessary to lower the patient or their
for the dentist to move into a different
head backwards in order to generate a
position or to move the OPMI. Often, it
better viewing angle.
is enough to simply move the patient's
For the patient, a comfortable, supine
For the lower jaw, most treatments can
position should be found. This can be
be performed when the patient is lying
improved through special padding and
head-and-neck supports.
head to the left or right. In many
Endodontic treatments are usually
cases, this provides a direct view of the
performed by indirect vision using a
treatment field.
mirror. Here, moving the patient's head
10°-20° degrees backwards is a good
2 Ergonomics
Figure 2.13
Figure 2.14
Figure 2.15
OPMI position
The S100 / OPMI pico with MORA
After establishing the basic position of
To ensure that the dentist can work
Tilting it along the vertical axis changes
interface is unique in this context: it
the dentist and the patient, the OPMI
in an ergonomically correct position,
the support position of the dentist,
enables tilting of the OPMI body in
needs to be positioned.
the OPMI must be set to the right
which results in less support for the
the lateral axis via the Mora interface
working distance or be equipped with a
pectoral girdle. Tilting the OPMI along
without also moving the eyepieces.
the lateral axis leads to a lateral tilt of
the head and thus to static overload of
In general, the OPMI is positioned at
the cervical spine.
an angle of 90° to the floor. Several
If the OPMI must be moved, it is
treatment situations require the OPMI to
possible to correctly configure the
be moved from this position.
eyepieces horizontally via a rotary plate.
Figure 2.16
2 Ergonomics
Functional design
OPMI assistance
Figure 2.18
Figure 2.17
Figure 2.19
As 12 o’clock is the most frequent
To enable efficient treatment, it is
To enable the work to be carried
This aspect must not be underestimated
seated position for the dentist during
advisable to position all necessary
out ergonomically, assistance
because it contributes to efficient
treatment, the treatment room must
instruments, materials and devices
tailored specifically to the needs of
workflow during a procedure.
be configured so that ample space is
around the dentist and the assistant
microdentistry is essential.
available behind the patient to ensure
in order to ensure that they are easily
not only that the dentist can sit there,
accessible. For this reason, the use
Instruments are frequently changed
but also that enough room is provided
of a cart is ideal. All instruments and
during a dental procedure. Because
for assistants to move to and fro.
materials required for a procedure can
dentists constantly look through the
be placed on them and made ready for
eyepieces, they cannot see the required
a procedure in advance.
instruments and materials, making it
necessary for the assistant to hand them
2 Ergonomics
Figure 2.20
Figure 2.22
The assistant must be able to see
It is important to point out two
Second, the correct and precise
their view away from the OPMI and thus
what the dentist sees in order to
aspects in regards to the hand over of
handover of the instrument from the
interrupts the workflow and leads to
adequately support him or her in the
assistant to the dentist is vital. Because
respective treatment situation. While
the handover position is outside the
co-observation tubes, are available in
First, to clearly communicate when
dentist's field of view, the instrument
Because assistants have to carry out
the vast majority of cases, it is better to
a used instrument is being returned,
must be given to the dentist with
multiple procedures including aspiration
have a monitor with the video image
which new instrument is needed and
the correct orientation relative to the
of the patient’s mouth, it is beneficial if
from a video camera connected to the
when it should be handed to the dentist.
treatment field and with the right grip
they can receive and pass an instrument
OPMI. This ensures that the assistant
This can be verbal communication,
position. If not, there is a certain risk of
with the same hand at the same time.
can optimally use the OPMI image to
or increasingly non-verbal when the
injury to the patient as a result of sharp
provide adequate support while keeping
dentists and the assistant have gained
or pointed instruments. Dentists often
experience in working as a team.
have to change their grip, which draws
the treatment field in view.
Figure 2.21
OPMI in endodontics
Author: Prof. Dr. José Aranguren Cangas
Dr. Manor Haas
Dr. Tony Druttman
74 Magnification in endodontics
Working magnification
75 Uses of the OPMI in endodontics
76 Microendodontic instruments
77 Ultrasonics
Ultrasonics tips
Uses of ultrasonics in endodontics
78 Mirrors
Micro instruments Files with a handle
Stropko syringe
Examination of the external surface of the tooth
Identification of the floor
of the pulp chamber
Removal of coronal restorations
Preservation of tooth structure
Assessement of canal cleanliness
after preparation
Identification of internal cracks
Canal location
Calcified canals
Evaluation and management
of perforations
Obturation of the canal
Non-surgical retreatment
Uses of the OPMI
in non-surgical retreatment:
Apical plug with MTA
File evaluation
94 Endodontic root-end surgery
3 OPMI in endodontics
In the 21st century the OPMI plays a vital role in endodontics
and endodontists have led the way in embracing the OPMI
into daily clinical practice. Endodontic treatments can be very
challenging due to the complexity of the anatomy of the root
canal system. In the past root canal treatment was performed
predominantly by feel. With the aid of the OPMI, structures
can be seen that remain hidden to the naked eye and treatment can be carried out with far greater precision and predictably than ever before. Microscopy in endodontics has become
a way of life.
Figure 3.1
3 OPMI in endodontics
Magnification in endodontics
Figure 3.2a magnification 3.5x
Figure 3.2b magnification 5.1x
Working magnification
Figure 3.2c magnification 8.5x
Figure 3.2d magnification 13.6x
Figure 3.2e magnification 21.25x
In endodontics we are used to
working with 8.5x magnification.
However, if we have to work in
the canal or we want to record the
treatment we need 13.6x or 21.25x
Uses of the OPMI in endodontics
1. Examination of the external surface of the tooth
2. Removal of coronal restorations
Magnification factors
3. Preservation of tooth structure
4. Identification of the floor of the pulp chamber
0.4x - 0.6x
5. Location of sclerosed canals
This is used mainly for periapical surgery
6. Identification and orientation of curvatures in the radicular access
7. Identification of internal cracks, ledges and blockages in the root canal
More common magnification
1.6x - 2.5x
Used to visualize fine details and for documentation.
8. Evaluation of canal cleanliness after preparation
9. Ensure optimal obturation
10. Assessment of existing root fillings
11. Identification and management of perforations
12. Assessment of coronal leakage
13. Evaluation of endodontic instruments after use
14. Removal of root filling materials in non surgical re-treatment
15. Management of soft and hard tissues in surgical re-treatment
3 OPMI in endodontics
Micro endodontic instruments
Figure 3.3 Accurate positioning of an LN bur (0.5mm dia) while working with indirect vision
Figure 3.4 Ultrasonic preparation of the isthmus in a lower molar
under an OPMI
using ultrasonic k-files
Figure 3.5a EndoSuccess™ ET 25
Figure 3.5b EndoSuccess™ ET 25
ultrasonic tip straight
ultrasonic tip curved
Ultrasonic tips
Ultrasonic instrumentation is a vital
There are many different ultrasonic tips
part of the armamentarium needed
on the market. Some have a smooth
in primary and re-treatment cases,
surface, others diamond coated. Some
both surgical and non surgical. For
are rigid, while others are flexible to
endodontic uses, ultrasonic devices have
improve visibility. Even K-files can be
to be set at a lower power range than
used ultrasonically. The tips can be used
for other applications such as scaling,
with irrigant or dry. The advantage of
otherwise the delicate tips can fracture
ultrasonic instruments over conventional
handpieces is one of visual access.
Uses of ultrasonics in endodontics
1. to refine access cavities
Because of the level of precision that
2. canal location (especially where can be achieved when using the OPMI,
canals are sclerosed)
special instruments are required. These
3. refinement of canal preparation
include instruments that help to identify
4. removal of fractured instruments
structures and allow the more accurate
from canals
removal of tooth tissue by improving
5. post removal
visual access.
6. root end preparation in endodontic
3 OPMI in endodontics
Figure 3.7 06 handfile attached through the hole in the handle using Hu Friedy
Figure 3.6 Fig HR mirrors in Size 000, 0, 4 and 8
Figure 3.8a Fucsin
Figure 3.8b Methylene blue
Figure 3.8c Fluorescein
DP18L locking tweezers
Micro-instruments Files
with a handle:
Mirrors are essential to the use of the
for documentation as the mirror can be
Special instruments for working with
Very few standard burs can be used
The dyes are used to find fractures, or
OPMI because there are very few areas
rested against a rubber dam clamp for
the OPMI include the micro-opener and
with the OPMI, because usually the
cracks and hidden canals.
is a red-orange dye mainly used in
of the mouth that can be viewed by
stabilization. Small diameter mirrors are
the micro-debrider. Both instruments
shank is too short and visual access is
The two most important dyes are
calcified canals. With the xenon
direct vision. It is therefore important
very useful where access is limited as the
are very useful as they allow working in
impaired by the head of the handpiece.
Fluorescein and methylene blue.
source, organic tisue is dyed
that silver fronted mirrors are used
mirrors can be moved further away from
the canal with unimpaired visual access.
It is important therefore to use long
Fucsin can also be used.
fluorescent green.
so that there is no distortion of the
the operating filed. Size 000 (10mm)
reflected image. Because it is necessary
and size 0 (14mm) are very useful for
The micro - opener is used to look
to have the maximum amount of light to
upper second and third molars. Micro
for the entrance of the canal It may
is used in crack diagnosis and apical
illuminate the depths of the root canal,
mirrors of different shapes are used in
also be useful in the identification of
surgery, is a blue dye (from light-dark),
it is also important that as little light as
surgical endodontics to examine the cut
a bifurcation or a ledge. The micro-
and dyes the surface of the fractured
possible is absorbed by the surface of
root face and crypt.
debrider which is based on a Hedstrom
organic tissue dark-blue. It is very
file is used to remove tissue from the
useful in apical surgery as it dyes the
wall of the canal or root filling material.
perimeter of the root and the different
the mirror.
shank burs so that tip of the bur can be
controlled precisely.
There are three different mirror
•Methylene blue
apical foramina.
Regular hand instruments can also
be used by attaching them to locking
tweezers (Figure 3.11).
•HR mirrors
Stropko syringe:
This instrument is really useful for drying
To work with the OPMI, we need at
least rhodium mirrors, these reflect 75%
of the light. Standard mirrors result in
Figure 3.9a rhodium mirror
the canal at a precise point. It is used in
micro apical surgery for drying the canal
before obturation.
double images and a loss in definition.
Figure 3.10 A selection of slow and high
speed burs used for endodontic access cavity
HR mirror have the highest reflectivity
Figure 3.11 Hu Friedy DP18L locking tweezers
on the market today (99.9%).
inserted into a standard hand file
Mirror size is also important. While size
4, the standard size (22mm dia) are
used in most situations, other sizes are
available. Size 8 (30mm) is very useful
Figure 3.9b HR mirror
3 OPMI in endodontics
Examination of the external surface of the tooth
Figure 3.12 crack through mesial marginal ridge (arrow)
Figure 3.13 vertical root fracture seen through the microscope while retracting
Figure 3.14 vertical root fracture seen below crown margin
Figure 3.15 external resorption
gingival margin
Prior to starting endodontic treatment
the OPMI is particularly useful for
examination of the external surface of
the tooth. Caries can be identified in
areas that are difficult to see without
magnification and illumination. Vertical
and horizontal cracks, root fractures and
external root resorptions are more easily
identified with an OPMI
Figure 3.16 Examination of crown margin
3 OPMI in endodontics
Figure 3.17 Sclerosed pulp chamber in lower left first molar due to a
Figure 3.18a View of a pulp stone as seen via the OPMI.
deep restoration and recurrent caries
Note the rough pulp floor surface, indicative of pulp stones
Figure 3.19a Radiograph of lower left second molar in figure 3.19b and 3.19c
Figure 3.18b This is the view of the above access after the pulp stones were
Figure 3.19b Composite is partially removed to expose the floor of
Figure 3.19c The floor of the pulp chamber has been revealed
removed with micro-ultrasonics or slow-speed, surgical-length, round burs.
the pulp chamber in an endodontic re-treatment case
in the distal half of the access cavity
Removal of coronal restorations
Preservation of tooth structure
Increasingly composite is replacing
The removal of excessive amounts
Note the smooth floor
Identification of the floor of the
pulp chamber
Insult to the pulp (caries, cracks,
between calcifications in the pulp
amalgam as the material of choice for
of tooth structure, both coronal and
restorations) can make the floor of the
chamber (i.e. pulp stones) and the
coronal restorations. As the colour of
radicular leads to weakening of the
pulp chamber difficult to identify
floor of the pulp chamber can be
composite can be very similar to that
tooth. This can result in fracture of
(Figure 3.17). Using the OPMI it is
distinguished by colour and texture.
of dentine, its removal can be difficult
either the coronal restoration or
possible to distinguish between pulp
Medium to high magnification is
without a microscope (Figures 3.19a
root fracture. The OPMI allows for
stones, reparative dentine and the true
and 3.19b).
the strategic removal of tooth tissue
floor of the pulp chamber. Differences
during preparation and refinement of
the access cavity, the removal of core
materials in re-treatment cases and the
preparation of canals with a non-circular
cross section.
3 OPMI in endodontics
Figure 3.20a Pre-operative radiograph of lower left
Figure 3.20c debris left in the distal canal of a lower first molar after instrumentation with
first molar
rotary instruments and irrigation.
Figure 3.20b Post-operative radiograph of lower left
Figure 3.20d distal canal obturated
Figure 3.21 Radicular crack
first molar
Assessment of canal cleanliness
Identification of internal cracks
after preparation
The dentist should always look for
Not all canals are circular in cross section
preparation and post instrumentation
internal vertical coronal and radicular
and when oval canals are prepared
irrigation and any remaining debris
cracks and fractures when using the
with rotary instruments, debris can
removed before obturation (Figure
OPMI. These would be difficult or
easily be left behind. The OPMI can be
impossible to detect without the high
used to evaluate canal cleanliness after
magnification and illumination provided
by the OPMI.
3 OPMI in endodontics
Figure 3.22a Upper central incisor with unusual
Figure 3.22b Pre-operative radiograph of tooth 21
Figure 3.22c Post-operative radiograph showing
Figure 3.24a Pre-operative radiograph of lower
Figure 3.24b The lingual canal has been identified
Figure 3.24c Lingual canal preparation started
canal anatomy. The canals could be identified
shown in fig 3.22a
the intricacies of the canal anatomy
left first premolar rotated through 90 deg.
after the buccal canal preparation has been
with pre-curved hand files, at 90 deg to the buccal
using the OPMI at high power and maximum
Note the bifurcation of the canal on the middle
completed, an 06 hand file has been precurved
canal, and the angle reduced with ultrasonically
third of the root
and positioned into the lingual canal with the aid
energised k-files and preparation completed with
of the OPMI
nickel titanium rotary files
Figure 3.23 Floor of the
pulp chamber viewed
through an OPMI. Note
how easy it is to locate the
calcification over the MB2
Canal location
•Small canals can be located using the
OPMI at higher magnification and
The root canal anatomy of teeth can
with medium to high illumination.
be very variable and missed canals are
•MB2 canals are often sclerosed in
a major cause of failure of root canal
the pulp chamber and require small
treatment. The OPMI plays a vital role in
diameter, surgical-length, slow- speed
helping to identify accessory canals at
and round burs or ultrasonic tips.
whatever level they may be. Commonly
For improved precision the tip of the
missed canals are the MB2 canal in
Figure 3.24d Post-operative radiograph showing
Figure 3.24e Both canals obturated using warm
bur or ultrasonic instrument should
maxillary molars and to a lesser degree,
how the lingual canal has been straightened
vertically compacted gutta percha
be visible at all times during canal
the mid-mesial canal in mandibular
location. Flexible ultrasonic tips which
molars, buccal canals of lower incisors
have been pre-curved are particularly
and second and third canals in
useful in these situations.
•Once the canals are located, very small
hand files should be used to negotiate
3 OPMI in endodontics
Figure 3.25a MB2
Figure 3.26a
visible as a white spot,
MB2 and MB3
too small for a 0.06 file
canals identified
to enter
during access
Figure 3.25b MB2
canal has been
chased with a 0.5mm
rosehead bur and
prepared with rotary
Figure 3.25c MB1 has
been obturated and
sealer has been forced
into the MB2 canal
indicating that MB1
and MB2 canals join
Figure 3.25a
Figure 3.26b
Radicular access
into MB2 and
MB3 canals
prepared with
Calcified canals
0.5 mm rosehead
Figure 3.25b
One of the greatest challenges in
endodontics is locating canals, especially
calcified canals. Canals sclerose from
coronal to apical and several millimetres
of sclerotic dentine may have to be
removed before the canal is found.
The OPMI tremendously facilitates this
important part of endodontic treatment.
Use medium to high magnification and
maximum illumination when searching
for small canals.
Figure 3.25c
3 OPMI in endodontics
Figure 3.29a
Figure 3.27a Upper left first molar with sclerosed canals, pre-operative
Figure 3.28a Sclerosed canal in lower incisor
Figure 3.29b
Figure 3.27b Tooth above post-operative radiograph
Figure 3.28b The gradual removal of tertiary dentine reveals the
entrance to the canal
Figure 3.29c
Figure 3.29a Canal and perforation
after post removal
Evaluation and management
Figure 3.29b Root filling and
of perforations
collagen matrix (indicated by arrow)
Figure 3.29c MTA perforation repair
The ability to visualize and determine
the exact extent of a perforation helps
determine treatment options and
Figure 3.27c Tooth above showing sclerosed tertiary dentine in the coronal
prognosis and makes it possible to repair
part of the palatal root canal. 4-5mm of tissue had to be removed before an
entrance into the canal could be found
Figure 3.28c sclerosed lower right central incisor
the site.
3 OPMI in endodontics
Figure 3.30 Obturation of circular canals
Figure 3.32a Fig Pre-operative radiograph of upper right first
premolar showing metal posts
Figure 3.33a Pulp stone in the palatal canal adjacent to the root filling
Figure 3.33b Pulp stone partially removed from canal
Figure 3.34 Removal of tissue from the isthmus
Figure 3.35 Failed root treatment where the floor
between the mesial canals of a lower molar
of the pulp chamber has not been exposed
Figure 3.36 MB2 canal has been missed
using ultrasonically energised K-files
Figure 3.31 Obturation of oval canal
Figure 3.32b Intracoronal removal of the post and core while
retaining the crown. The post is being removed with ultrasonics
Uses of the OPMI in
non-surgical re-treatment:
Obturation of the canal
Non-surgical re-treatment
Most canals are not circular in cross
Endodontic re-treatment is considered
section and obturating them under the
to be one of the most challenging
control of the OPMI ensures that the
procedures in endodontics. In these
•location of missed canals
canals are filled with the root filling
situations the OPMI is essential.
•removal of existing root filling
•removal of existing restorations, posts
material in all dimensions.
and core materials (especially useful
for removal of composite cores
•evaluation of the condition of the
•evaluation of the canal walls for cracks
canals after removal of root filling
•overcoming ledges and blockages
•removing fractured instruments
•removal of necrotic tissue and
•evaluation and repair of perforations
residual root filling materials after
re-preparation of the root canals
3 OPMI in endodontics
Figure 3.37a Pre-operative radiograph of
Figure 3.37b Post-operative radiograph of the
Figure 3.37c Endo Success ET 25 ultrasonic tip has
upper right first molar tooth with two fractured
same tooth with the instruments removed using
been pre-curved to improve visual access for the
ultrasonic instruments controlled under the
removal of fractured instruments
OPMI. Note that the canals were curved in a
bucco-palatal direction.
Figure 3.39 apical plug with MTA
Figure 3.40 a distorted rotary file viewed at high
magnification under the OPMI
Figure 3.38a Pre-operative radiograph of two lower
Figure 3.38b Post-operative radiograph of lower
Figure 3.38c The OPMI was used to position and
incisors with apically placed silver point root fillings
incisors with silver points removed
engage two Hedstrom files around the silver points
Apical plug with MTA
File evaluation
MTA is an excellent material for
Evaluation of stainless steel hand and
repairing perforations and sealing
NiTi rotary files under magnification and
large apical foramina. The material
enhanced illumination is an excellent
can be placed with a great deal of
and quick way to determine if files are
control when using the OPMI to
weakening and are at risk of separating.
ensure that there are no voids
The dentist should look for overwound
(Figure 3.36).
file flutes (flutes too close to each other)
or unwinding flutes (the space between
the flutes increases, which makes it
appear shiny under enhanced lighting).
Identifying this helps reduce the chance
of file separation. It is much easier to
identify these weak points in a file under
3 OPMI in endodontics
Endodontic root-end surgery
Figure 3.41b Complex anatomy of
Figure 3.41c X-ray after surgery
root canal system
Thanks to the improved visualization
to diagnose/locate root-end micro-
microsurgical instruments, this
procedure can be performed much more
done more precisely and conservatively
of apical bone removal/osteotomy size
with use of micro-ultrasonic tips made
does not need to be large when using
specifically for surgery. For this, one
the OPMI. Hence, the procedure could
should use high magnification and
be considered as minimally invasive.
high illumination.
improves hard-tissue healing and
isthmuses can be visualized under the
optical magnification
•Root-end canal preparation can be
conservatively. For instance, the amount
•The smaller apical osteotomy / access
Figure 3.41a After root-end resection,
•Using an OPMI enables the dentist
provided by the OPMI along with
success rates.
•The OPMI enables the dentist to locate
•Flaps are improved with the ability to
make incisions more precisely with
•Suturing under the OPMI should be
isthmuses (often infected) joining
more precise and less traumatic. This
adjacent canals (ie isthmus between
is made possible since very fine sutures
MB1 and MB2 in maxillary molars or
(i.e. 6-0) could be better visualized
MB and ML canals in lower molars)
under the OPMI. This is especially
•The OPMI enables the identification of
important in the aesthetic area.
fractured instruments at the root apex.
3 OPMI in endodontics
Figure 3.42 Periapical lesions in 21 22 (computer tomography)
Figure 3.45 Incision line
Figure 3.46Intrabony defect found after flap elevation
Figure 3.43 Fistula in 22 area
Figure 3.44 Micro-scalpel for atraumatic incision with tissue preservation
Figure 3.47 Purulent discharge
Figure 3.48 Maxillary left lateral incisor apicoectomy (after
enucleation of lesion)
3 OPMI in endodontics
Figure 3.49 Checking with micro mirror
Figure 3.50 Ultrasonic instrumentation
Figure 3.51 Obturation of the canal by MTA ProRoot
Figure 3.52 Suturing the wound and 3 days after surgery.
Note debris over mucoae due to heavy smoking
Figure 3.53 First intention healing is a fast healing process of a small wound
Figure 3.54 7 days after surgery
Figure 3.55 1 year after surgery
Figure 3.56 X-ray after 1 year
because of atraumatic re-approximation of the incision edges
OPMI in periodontology
and implantology
Authors: Dr. Kristina Badalyan &
Dr. Rino Burkhardt
105 Do we need an OPMI
in periodontal and implant
106 What are the advantages
and disadvantages of
the use of an OPMI
in periodontology and
110 What does the
“microsurgical concept”
consist of?
122 Which are the first steps to
getting used to working with
the OPMI?
126 How can you acquire
expertise in periodontal
and peri-implant
128 Which are the common
errors in the use of the
OPMI in surgical practice?
4 OPMI in periodontology and implantology
Do we need an OPMI in periodontal
and implant therapy?
Undoubtedly, microscopic enhanced periodontal and implant
visual rather than tactile control. This altered clinical situation,
therapies have reshaped clinical practice and created a
combined with the impaired manoeuvrability of the OPMI,
potential for higher standard of care. Throughout the world,
requires a process of readjustment by the surgeon, which in
the benefits of the OPMI in these specialties are clearly evident
turn can only be achieved by the appropriate training.
from the positive feedback from clinicians and patients alike.
Additionally, the advantages are supported by several high
It is the aim of the chapter
ranking clinical studies in the evidence hierarchy.
•to describe the use of the OPMI in periodontology and implantology for diagnostic as well as therapeutic reasons
Despite the positive results in prospective comparative
•to list the benefits of an OPMI-enhanced treatment
studies, the OPMI is experiencing a slow acceptance in the
for patients and clinicians
periodontology and implantology specialties.
•to give practical recommendations for beginners and those
who are interested in working with magnifying eyeglasses to
What then can be the reason for the delay in taking
encourage clinicians to take advantage of the use of an
advantage of such microsurgically modified therapies? The
OPMI in daily clinical practice.
main reason is that most of the surgeons do not adapt to
the use of the OPMI and those who have been using OPMIs
successfully, have not made adequate in-depth practical
recommendations to help other colleagues to overcome
their initial problems. Working with magnification requires
the clinician to adjust to a small field of view and learning to
look in one direction whilst the hands are working in another
direction. Additionally, the minimal size of tissue structures
and suture threads requires a guidance of movements by
Figure 4.1
4 OPMI in periodontology and implantology
What are the advantages and disadvantages
of the use of an OPMI in periodontology
and implantology?
Figure 4.2
Figure 4.3
Recession coverage: Macro- and microsurgery in comparison*
Microsurgical recession coverage (B). B1) immediately after the
Macrosurgical recession coverage (A). A1) immediately after the
surgical intervention, B2) corresponding angiographic evaluation
surgical intervention, A2) corresponding angiographic evaluation
after the intervention, B3) healing after 7 days, B4) angiographic
after the intervention, A3) healing after 7 days, A4) angiographic
evaluation after 7 days
evaluation after 7 days
To ensure proper diagnosis and
and biofilm, the evaluation of furcation
suture diameters. The latter is not only
It has been shown that the incidence
therapeutic purposes. From a practical
treatment planning which are
entries of molars, the recording of root
less traumatic, but also reduces the
and severity of complications and pain
point of view, there a few areas of
fundamental requirements in all kinds of
surface characteristics (enamel pearls,
tension which can be applied to the
following periodontal surgery are
the oral cavity which may be difficult
periodontal and implant therapies, the
concavities, grooves) and many other
tissue margins during wound closure.
correlated well with the duration of the
to access with an OPMI, limiting its
required information must be obtained
findings which are essential for a proper
However, finer threads are more prone
surgical procedure, an argument used
application. Under these circumstances
by clinical examination and additional
to breakage than thicker ones and may
by opponents of periodontal and peri-
and in surgical interventions which
rupture before tissues are torn.
implant microsurgery.
require a frequent change of position,
appropriate image-guided diagnostics.
Regarding the former we can only
Another enormous advantage
record what we see. Accordingly, the
of an OPMI-supported approach
These advantages are especially useful
Studies comparing micro- and
better we see, the more precise our data
in periodontology relates to the
when dealing with fragile tissues with a
macrosurgical approaches show no
for the diagnostic result will be.
enhanced visual acuity associated with
limited vascular network such as
difference in this respect.
magnification and illumination while
the interdental mucosa. The use of
In a recent experiment the use of an
performing clinical interventions such as
an OPMI greatly improves the surgical
In view of this situation, there are no
OPMI enabled dentists to find a greater
defect debridement, root planing or any
access to interdental or interimplant
clinical contraindications for the use
number of defects than with either
other surgical procedure which requires
spaces. These delicate and narrow soft
of an OPMI in periodontal and implant
magnifying loupes or the naked eye.
a controlled manipulation of the delicate
tissues can be sharply dissected and
surgery, for diagnostic as well as
Additionally, the OPMI users profited
oral soft tissues.
preserved using microblades with
the use of loupes may be preferable.
the aid of clear magnified vision,
most from an ergonomic posture
and did not report any neck or back
A microsurgical approach improves
thus reducing trauma and facilitating
pain. This comparative study clearly
tissue preservation and handling while
accurate wound closure (Figure
demonstrated the beneficial effects of
using specific flap designs to access
4.4). It is generally recognized that
using an OPMI as a diagnostic tool.
the defects. It optimizes flap mobility
wound healing is improved in a sealed
It may be of value in the location and
in order to achieve primary closure
environment with minimal levels of
visualization of a variety of substances
or to cover mucosal recession, and
bacterial contamination and optimal
and defects. These include, for example
it reduces the trauma caused to the
stability of the wound margins.
the detection of subgingival calculus
tissues by enabling the use of smaller
4 OPMI in periodontology and implantology
Figure 4.4
Left: Buccal view of primary wound closure with fine
suture threads after modified papilla preservation flap
Right: Occlusal view of the same site. Note the intact
mucosal surface of the delicate col area
4 OPMI in periodontology and implantology
What does the “microsurgical concept” consist of?
Correct instrument handling
Incorrect instrument handling
Figure 4.5
Left: Microsurgical instrument which can be
precisely rotated by the thumb, index and middle
Figure 4.6 a
Basic kit of microsurgical instruments for
periodontal and peri-implant surgery: A) needle
holder, B) scissor, C) surgical forceps, D) anatomical
Right: Conventional instrument without rounded
forceps and E) blade holder
handle. Its rotation can only be performed by
turning the wrist, which is a less precise movement
The ongoing development of OPMIs,
neurosurgery and are therefore,
a precise lock that features a locking
between the needle holder jaws. This
when the instrument lies in the hand
the refinement of surgical instruments,
inappropriate for the use in periodontal
force of no more than 50 g (0.5 N).
benefit must be weighted against
without any pressure. Before purchasing
the production of improved suture
and implant plastic surgery. As the
High locking forces generate tremor,
the potential damaging effects of the
a set of microsurgical instruments,
materials and the emergence
instruments are primarily manipulated
and low locking forces reduce the
teeth on suture material. Smooth jaws
appropriate time should be allowed for
of suitable training laboratories have
by the thumb, index and middle fingers,
security of the lock. Appropriate sets
without teeth cause no demonstrable
selection and clinical testing. Ill-fitted,
played a decisive role in the worldwide
their handles should be rounded, yet
of steel or titanium instruments for
damage to 6-0 monofilament nylon
imprecise or damaged instruments will
establishment of microsurgical
provide traction so that finely controlled
periodontal surgery are available from
sutures, whereas needle holder jaws
negatively influence the performance
techniques. The three elements,
rotating movements can be executed.
different manufacturers.
with teeth (7000/sq.in) markedly
and make a microsurgical procedure
magnification, illumination and
The rotating movement of the hand
reduced the suture breaking strength.
almost impossible. It is recommended
instrumention, are called the
from two o’clock to seven o’clock
A basic set comprises a needle holder,
Additionally, the sharp outer edges of
to choose an instrument brand from a
microsurgical triad, the combined use of
(for right-handed persons) is the most
micro-scissors, micro-scalpel holder,
the needle holder jaws must be rounded
company which is already familiar with
which is the prerequisite for improved
precise movement that the human body
anatomical and surgical forceps and a
to avoid breakage of fine suture
the production of dental or oral surgical
accuracy in surgical interventions.
is able to perform. The instruments
set of various elevators (Figure 4.6a -
materials. When the needle holder jaws
instruments. These manufacturers
Without any of these, microsurgery is
should be approximately 18 cm long
4.6b). In order to avoid sliding of the
are closed, no light must pass through
are more likely to be familiar with the
not possible. The first two have already
and lie on the saddle between the
thread when tying the knot, the tips of
the tips. Locks aid in the execution of
typical aspects of an intra-oral mucosal
been described at the beginning of this
operator’s thumb and the index finger
the forceps have flat surfaces or can be
controlled rotation movements on the
surgery and incorporate the above-
book, so let us now focus directly on
and simultaneously be slightly top-heavy
finely coated with a diamond grain
instrument handles without pressure.
mentioned instrument characteristics in
the instruments.
to facilitate accurate handling (Figure
that improves the grip by which the
The tips of the forceps should be
their production (Hu-Friedy, Chicago,
4.5). In order to avoid unfavorable
needle holder holds a surgical needle.
approximately 1 mm to 2 mm apart,
USA). Such basic instrument kits
metallic glare under the OPMI
The configuration of the needle holder
Technical aspects of instruments
Proper instrumentation is of
illumination, the instruments often have
jaw has considerable influence on
fundamental importance for a
a coloured coating surface. The weight
needle holding security. The presence
microsurgical intervention. While
of each instrument should not exceed
of teeth in the tungsten carbide inserts
various manufacturers have sets of
15 g to 20 g (0.15- 0.20 N) in order to
provides the greatest resistance to
microsurgical instruments, they are
avoid hand and arm muscle fatigue. The
either twisting or rotation of the needle
generally designed for vascular and
needle holder should be equipped with
can be recommended for all kinds
Figure 4.6b
Rounded handle of the blade holder allows
a finely rotating movement of the fingers and
of periodontal and implant surgical
precise guidance of the surgical microblade
4 OPMI in periodontology and implantology
A Macrosurgical blade, No 15
B Macrosurgical blade, No 15c
C Periodontal microblade straight
D Periodontal microblade curved
Figure 4.7
Figure 4.8 Clincial situation represents the preparation of the buccal mucosa in
Figure 4.10 Papilla preservation technique.
Macro- and microsurgical scalpel types from different ma-
the area of the root prominence. Note the specific curved shaft of the scalpel to
Primary closure of palatal papillae with fine
nufacturers (A & B Swann Morton Ltd., Sheffield, UK;
reduce the risk of accidental mucosal penetration
suture materials (7-0 polypropylene)
C & D Sharpoint™ by ©Angiotech, Inc., Vancouver, BC,
Various shapes and sizes of micro-
In order to prevent damage, micro-
scalpels from the disciplines of
instruments are stored in a sterile
ophthalmology or plastic surgery
container or tray. The tips of the
(Figure 4.7) can be used and
instruments must not touch each
complement the periodontal
other during sterilization procedures or
basic instrument sets, additionally
transportation. The practice staff should
supplemented with fine chisels,
be thoroughly trained in the cleaning
raspatories, elevators, hooks and
and maintenance of such instruments,
suction tips (Figure 4.9).
as cleaning in a thermo disinfector
without instrument fixation
can irreparably damage the tip of these
delicate microsurgical instruments
Figure 4.9
Fine working end of a microsurgical
elevator. The underlying stamp illust-
Figure 4.11
rates the small size of the instrument
Example of container or tray system to store the fragile microsurgical instruments and to prevent them from damage during washing, sterilization and
4 OPMI in periodontology and implantology
Figure 4.12 Before microsurgical crown lengthening
Figure 4.14 After microsurgical crown lengthening (two months postoperatively)
Suture materials
Suture materials and techniques
a wound may significantly enhance
are essential factors to consider in
the susceptibility to infection. Hence,
microsurgery. Wound closure is a key
it is obvious that needle and thread
prerequisite for healing following
characteristics also influence the wound
surgical interventions and most
healing and surgical outcome.
important to avoid complications. The
most popular technique for wound
closure is the use of sutures that
stabilizes the wound margins sufficiently
and ensures a proper closure over a
defined period of time. However, the
Figure 4.13 Microsurgical wound
penetration of a needle through the
closure with 8-0 sutures provides a
soft tissue in itself causes trauma and
precise flap adaptation
the presence of foreign materials in
4 OPMI in periodontology and implantology
Figure 4.15
Figure 4.16
Figure 4.17 Surgical site before
Flattened needle body ensures a firm seat of the
Left: Sharp tip (spatula) of a microsurgical needle
microsurgical wound closure
needle in the needle holder and prevents the
(200x magnification)
needle from twisting to either one or the other side
Right: Damaged needle tip after touching the enamel
surface of a neighbouring tooth
Needle characteristics
Buccal releasing
3/8 curvature, cutting needle, length 7mm
3/8 curvature, cutting needle, length 7mm
3/8 curvature needle, cutting needle, length 6mm
3/8 curvature, cutting needle, length 11mm,
3/8 curvature, cutting needle, length 11mm,
3/8 curvature, cutting needle, length 13mm
3/8 curvature, cutting needle, length 13mm
Characteristics of the needle
Needles consist of a swage, body and tip
or less traumatic penetrations. In order
in the anterior aspect requires needle
and differ in their material, length, size,
to minimize tissue trauma in periodontal
lengths of 10 mm to 13 mm, and for
tip configuration, body diameter and the
microsurgery the sharpest needles,
closing a buccal releasing incision, needle
manner of connection between needle
namely reverse cutting needles with
lengths of 5 mm to 8 mm are adequate.
and thread. In atraumatic sutures the
precision tips or spatula needles with
To guarantee perpendicular penetration
thread is firmly connected to the needle
micro tips are preferred (Figure 4.16). The
through the soft tissues that prevents
through a press-fit swage or inserted
shape of the needle can be straight or
tearing an asymptotic curved needle is
in a laser-drilled opening. There is no
bent to various degrees. For periodontal
advantageous in areas where narrow
difference concerning stability between
microsurgery the 3/8” circular needle
penetrations are required (e.g. margins of
Interdental suture,
molar area
3/8 curvature, cutting needle, length 16mm
DSM 16 /DSMF 16
the two attachment modalities. The body
generally ensures optimum results. The
gingivae, basis of papillae). To fulfill these
Crestal incisions
of the needle should be flattened to
lengths, as measured along the needle
prerequisites for ideal wound closure at
3/8 curvature, cutting needle, length 11mm
prevent twisting or rotation in the needle
curvature from the tip to the proximal
least two different sutures are used in
3/8 curvature, cutting needle, length 13mm
holder (Figure 4.15). The needle tips
end of the needle lock, extend over a
most surgical interventions.
differ widely depending on the specialty
wide range. For papillary sutures in the
Table 4.1 serves as a basic guide to select
3/8 curvature, cutting needle, length 7mm
in which they are used. Tips of cutting
posterior area needle lengths of 14 mm
the appropriate suture material.
needles are appropriate for coarse tissues
to 16 mm are appropriate. The same task
3/8 curvature, cutting needle, length 7mm
Interdental sutures,
front area
Interdental sutures,
premolar area
Papilla basis
Table 4.1
Ideal needle-thread combinations
(non resorbable) for the use in periodontal and peri-implant microsurgery
(Resorba GmbH, 90475 Nuremberg,
4 OPMI in periodontology and implantology
Figure 4.18
Example of a suture package with explanation of
the relevant notations, abbreviations, symbols and
signs (A Product name of specific suture, often
referring to the suture material, B diameter of the
suture thread, see Table 2, C suture material, D
curvature and length of the needle, E colour code
of the suture (facilitates the identification), F configuration of the needle tip, G composition of the
thread (monofilament / polyfilament), H pictogram
for absorbability / non absorbability and composition of the thread, I thread characteristics (text), K
needle length (measured from the tip to the end of
the needle), L configuration of the needle (manufacturer specific)
The characteristics of needle and
thread configurations are marked on
each suture package (Figure 4.18).
Suturing threads are classified
according to their thickness
European pharmacopoe
All suturing materials,
resorbable and
metric no.
American pharmacopoe
Figure 4.19 Surgical site three days post-
All suturing
except collagen
USP no.
suturing materials
(Table 4.2). Depending on the
manufacturers, it is important to
note that either the European or the
American nomenclature will apply.
USP no.
While the former follows a metric, the
latter follows an arbitrary classification
reveal the thickness of the thread.
However, the American products do
Table 4.2. Classification of suturing
materials (diameter of the threads)
system. European products strictly
comply with the European system and
not follow the classification according
to the diameter of the threads.
operatively before suture removal
Figure 4.20: In thicker tissues detected suture
filaments, bright colored alcian blue in the absence
of inflammatory reactions in the surrounding tissue.
The suture in the gingival tissues. No pronounced
inflammatory reaction. Alcian blue coloration.
Increase x50 (top) x 400 (below)
4 OPMI in periodontology and implantology
Characteristics of the thread
Figure 4.21 High magnification of suture placed to
Figure 4.22 Microclips as an alternative to mi-
close a skin wound
crosutures no mention of microclips in the text
tissue trauma. During suturing the
a distinct infiltrate. For that reason
versions and in monofilament versions
After suturing the thread will be
to the various types of suture materials
coating will break and the properties of
natural resorbable threads are generally
for finer suture materials. The capillary
encapsulated in connective tissues
and suturing techniques available in
The thread may be classified into either
the pseudomonofilament thread then
obsolete. Synthetic threads, however,
effect is limited and hardly exists for
and keep its stability for a longer
order to help obtain optimal wound
resorbable or nonresorbable materials.
corresponds to that of the polyfilament
are advantageous due to their constant
polyglactin sutures.
period. In 5-0 and thicker sutures the
closure and stability. Despite the many
Within these two categories the
threads. Additionally fragments of the
physical and biological properties.
monofilament threads are relatively stiff
technical solutions available on the
materials can be further divided into
coating may invade the surrounding
The materials used belong to the
and for that reason may impair the
market, there are no true alternatives
monofilament and polyfilament threads.
tissues and elicit a foreign body reaction.
polyamides, the polyolefines or the
patient’s comfort.
to suture threads which could prove
The bacterial load of the oral cavity also
requires special attention in the choice
Resorbable sutures
Nonresorbable sutures
polyesters that disintegrate by hydration
Polyamide is a commonly used material
into alcohol and acid. Polyester threads
for fine monofilament threads (0.1 mm
A substance with similar biological,
tissue adhesives are difficult to apply
their benefit in clinical practice. While
are mechanically stable and based on
to 0.01 mm) that show adequate tissue
but improved handling properties
in aqueous environments and critical
oral cavity the wound healing processes
Resorbable threads may be categorized
their different hydrolytic properties,
properties. Tissue reactions seldom
is polytetrafluoroethylene. Due to
to withstand wound margin tensions,
is uneventful thereby reducing the risk
as natural or synthetic. Natural threads
lose their firmness in different, but
occur except after errors in the
its porous surface structure the
the indication of microclips (Fig. 4.22)
monofilament threads should only be
is limited to the wound closure of
of the suture material. Generally, in the
of infection caused by contamination
(i.e. surgical gut) are produced from
constant times. A 50 percent reduction
polymerization process. Polyolefines, as
of the thread. As polyfilament threads
intestinal mucosa of sheep or cattle.
of breaking resistance can be expected
an alternative, are inert materials that
used with restriction in the bacterially
releasing or crestal incisons. Even if they
are characterized by a high capillarity,
The twisted and polished thread loses
after two to three weeks for polyglycolic
remain in the tissues without hydrolytic
loaded oral cavity (we recommend
are easy and fast to apply, the closing
monofilament qualities are to be
its stability within six to fourteen
acid and polyglactin threads, four weeks
degradation. Materials with excellent
avoiding the zone of aesthetic priority).
forces cannot be influenced by the
preferred. Pseudomonofilament sutures
days by enzymatic breakdown.
for polyglyconate and five weeks for
tissue properties are polypropylene
With the sophisticated surgical
surgeon and no sling or mattress sutures
are coated polyfilament threads with
Histological examinations confirmed
polydioxanone threads. The threads
and its most recent enhancement,
procedures applied today, there is a
can be executed.
the aim of reducing the mechanical
the inflammatory tissue reactions with
are available in twisted polyfilament
greater need for knowledge with regard
4 OPMI in periodontology and implantology
Which are the first steps in getting used
to working with the OPMI?
There is no doubt that, by using an
surgery, magnifications of 4x to 5x for
one can classify the familiarization
exercises, the second stage confronts
perform almost all surgeries under
OPMI the operating team is confronted
loupes and 8x to 20x for OPMIs appear
process with an OPMI into four different
the trainee with several new aspects
the OPMI with the highest accuracy
with a completely new environment
to be ideal depending on the kind
stages: 1) forming, 2) storming,
which in turn impair fluent clinical
possible. If there are not many
positional changes required during the
and the surgeons and assistants first
of intervention. As the depth of field
3) norming and 4) performing. The
work (storming phase). These include
have to adjust to the changed situation.
decreases with increasing magnification,
initial stage includes the first steps in
the inclusion of the assistant in the
surgery, such high-performing teams
Before starting with the clinical work
the maximum magnification for a
the training laboratory with the goal to
surgical procedure and the more
can accomplish a surgical intervention
on the patients the clinicians should
surgical intervention is limited to
automate the instrument handling
dynamic environment. The storming
within the same time or even faster than
become familiar with the impaired
about 12x to 15x, when dealing with a
and get used to the new conditions.
phase is necessary for the growth of the
without the use of an OPMI.
manoeuvrability of the OPMI, the
localized problem such as the coverage
It is important to allow enough time for
treatment team. It can be unpleasant
new requirements for hand-eye co-
of a single soft tissue recession or the
this initial familiarization process.
and exhausting and the speed of
For acquiring clinical expertise
ordination and the initial difficulties
interdental wound closure after guided
It should take place beyond the daily
progress in the familiarization process
in periodontal and peri-implant
which can arise from the new task-
tissue regeneration of an infrabony
busy schedule with patient treatments
with the OPMI may decrease. Some
microsurgery, time and training
sharing conditions between surgeon and
defect. A magnification range of 6x to
and not exceed the duration of 30
teams will never develop past this stage.
play an important role. Therefore,
clinical assistant. Without appropriate
8x seems appropriate
to 40 minutes per session. As an
training, periodontal surgery cannot
for clinical inspections or surgical
approximate guideline, a frequency of
Those that have successfully managed
automatically become better over
be performed with ease in a stress-free
interventions when the entire
three to four training units per week
the problems of the storming phase
time, which is just partly true. Once a
quadrant is under operation. Higher
is ideal to get familiar with the new
and found their workflow, now enter
daily routine is achieved and a surgical
magnifications of 15x to 25x are
technical equipment and the related
the norming phase. It is characterized
procedure can be performed with ease
Acquaintance with the OPMI in
more likely limited to the visual
restrictions regarding manoeuvrability.
by a mutual plan between the surgeon,
(performing stage), ongoing training
clinical practice
examination of clinical details, such as
Over and above the mere hours of
the chairside assistant and other team
is mandatory to further improve the
most clinicians believe that they
furcation morphologies or root surface
training, the structure of the exercises
members involved to further improve
dexterity of the surgeon’s hands. The
A substantial number of periodontists
pathologies. It is highly questionable if
is of the utmost importance to ensure
the workflow smoothly and effectively.
finely orchestrated sequential finger
have already adopted the use of
the previous use of loupe magnification
that maximum benefit can be gained
The norming phase consists of task-
movements need a stimulus coming
low magnification in their practices and
may help the beginner to get acquainted
and that the user’s expertise is improved
sharing and working for a common
from the brain. Otherwise, no further
recognize its great benefits. Loupes
to the OPMI. We strongly believe that
accordingly. This initial stage can last
goal. All of the team members have
apparent improvements in the micro
have the advantage over the OPMI in
it will not substantially shorten the
from one to several months and may
their allocated responsibilites and, more
hand movements can be expected (see
that they have a reduced technique
learning curve as other influencing
also include first clinical examinations on
importantly than in a conventional
sensitivity, they cost less and a shorter
factors play a more important role
surgical approach, the well-organized,
learning curve can be expected before
than magnification. Working under the
they can be used as a matter of routine.
OPMI does not only mean working with
When the trainee is able to manage
surgeon and chairside assistant
At present, it can only be speculated
higher magnification within an even
the basic clinical procedures with the
makes the team function. After a
how significantly the selection of
more restricted field of view, but it also
OPMI under laboratory conditions and
corresponding period of clinical
magnification influences the result
requires the user to become acquainted
they are increasingly becoming a matter
training, it is possible for some teams
of the operation. The magnification
with a totally new technical setup.
of routine, the learned skills can be
to reach the performing stage. These
recommended for surgical interventions
Similar to the formation of a new team
transferred to actual clinical practice.
teams are able to function efficiently
ranges from 2.5x to 20x. In periodontal
(Tuckman’s group development model),
Despite the previous familiarization
and effectively as a treatment unit and
interdependent relationship between
4 OPMI in periodontology and implantology
Figure 4.23
Clinical set-up for a surgical periodontal intervention with the OPMI. Note the opposite position of
the assistant when working with the co-observer
tubes (OPMI without sterile drape to demonstrate
the position of the OPMI components)
The importance of the hand-eye-
visual perception, including the ability to
At first sight it is not self-evident
Task-sharing between surgeon and
assistant due to the restricted peripheral
Therefore, it is recommended to get
brain coordination for fluent
see important patterns buried in visual
that the human hand is capable of
assistant (teamwork)
used to working in the centre of the
clutter and the ability to solve maze
performing finer movements than
movement of the OPMI can be
field of view. That way an upcoming
problems; they tested spatial memory;
the naked eye is able to control. In
In microdentistry, many clinical
In periodontal microsurgery, where the
Our lives are so full of commonplace
they tested the ability to perform under
macrosurgery, movements are controlled
procedures are performed with a
surgeon has very poor access, retraction
anticipated by the assisting person,
experience in which our hands are
stress. The tests were subdivided into
by the proprioceptive tactility of the
minimum number of position changes
is absolutely vital. The retraction should
which in turn facilitates the workflow.
so skillfully and silently involved that
three major headings: psychomotor
fingers and the palm. Since the adductor
of the operators. Focusing can easily
be done in different positions and must
Working with a co-observer tube is a
we rarely consider how dependent
abilities, complex visuospatial
and abductor finger muscles are
be achieved by moving the mirror
be devoid of all tremor or movement.
team approach and requires specific
upon them we actually are. One hand
organization and stress tolerance. After
relatively coarse, microsurgical training
towards or away from the objective
This is an exceptionally strenuous task
training of all included persons in a
consists of 27 bones and 39 muscles
processing their data, they looked
attempts to improve the fine-tuning
lenses. In periodontal and peri-implant
as the assistant is expected to maintain
simulated clinical environment.
which are responsible for the control
to see what the highest achievers in
of the motor muscles of the hand and
surgery both hands are used to hold
the same posture for a period of time
of the finger joints and the wrist. The
the programme had, that the lesser
arm and the training of the clinician’s
the instruments. Position changes are
which can extend to one hour or even
number of muscles exceeds by far the
surgeons lacked, or had less of, based
cognitive abilities as mentioned above.
more frequently required, increasing the
more. As flap retraction is extremely
number of degrees of freedom which
on the psychological tests. Guess what?
are provided by the finger joints - from a
The eyes have it!
biomechanical point of view a complete
demands on the operating team and
energy-consuming, the fatigue
A thread of a 10-0 suture has a diameter
necessitating ideal cooperation between
experienced by the assistant would
of only 20 μm to 29 μm. Therefore,
surgeon and assistant.
increase the chances of tremor as time
goes by.
This is not to imply that manual
tying a knot can only be controlled
dexterity is not important to
visually. When working under the OPMI
In all surgeries at least two operators
But likewise, for a dexterous
microsurgeons in performing their
with 10x through 20x magnification,
are involved, a surgeon and an
For an optimal workflow, magnification
manipulation, the role of the sensory
activities - they obviously are quite
just the instrument tips are visible and
assistant who supports the surgeon
is also required for the assisting person.
feedback in controlling the induced
significant, but the distinguishing
the appropriate suture material has a
in the most rudimentary tasks in the
motion must not be underestimated.
features of the superior practitioner
diameter five times smaller than a single
operation. However, the tasks that the
Only co-observer tubes allow the
Which are now the key issues for
are his/her ability to see the relevant
human hair.
assistant constantly repeats in almost
same view for surgeon and assistant,
precise hand and finger movements?
anatomical structures of the operative
all operations with varying levels of
allowing the assistant to direct the
Which body parts can and should be
site, even when this might not be
It is surprising, and not so obvious, how
skill are considered. These tasks include
suction tube accurately and keep the
trained? How do we become good
immediately visible, to quickly identify
much almost all physical skill flows from
flap retraction, suction, rinsing and
field of view clear (Figure 4.23). This
surgeons? The questions are serious
important landmarks in the incision
the maturation of motor skills under the
cutting the sutures. To guarantee a
also becomes an issue during suturing
ones and of intense interest to the
and to mentally organize multisensory
guidance of both visual and kinesthetic
continuous workflow during the surgical
when the air intake of the suction tube
people responsible for training surgeons
data and actions at any given point of
monitoring. Both the hand and the
intervention, a second assistant who
can easily aspirate the fine threads.
and microsurgeons. The Loyola Medical
the procedure so as to allow a smooth
eye develop as sense organs through
arranges the instruments is frequently
One disadvantage of this working
Center has investigated several aspects
and efficient sequence of responses.
practise, which means that the brain
desirable. Additionally, this second
configuration that must be mentioned,
of prospective surgeons related to
From this data we can conclude that
teaches itself to synthesize visual and
assistant monitors the well-being of
is the impaired manoeuvrability of the
their predictive value to become good
appropriate microsurgical training must
tactile perceptions by making the hand
the patient. Depending on the working
operating team, since each movement
surgeons. They looked at manual
not only focus on the pure psychomotor
and eye learn to work together.
configuration (loupe, video screen or
of the surgeon must be compensated
speed, fine motor coordination, and
skills but also on the perceptual abilities
co-observer tubes), this task might be
for by the same movement of the
bimanual sequencing; they looked at
of the trainee.
difficult to perform by the chairside
assistant in the opposite direction.
4 OPMI in periodontology and implantology
How can expertise be acquired in periodontal
and peri-implant microsurgery?
Most microsurgical training programmes
few tenths of a milimeter can make a
incisor to the last molar and the three
are related to beginners, focusing on the
surgical intervention impossible.
dimensionality of the oral mucosa. For
forming phase (mentioned above). They
Its physiological basis is uncertain,
completion of the initial phase, the
are designed to give an insight into the
but it is important to be aware of the
trainee is given a booklet with exercises
world of magnification, accompanied by
causes in order to prevent them. The
based on increasing levels of difficulty.
technical information about the OPMI
body posture must be natural, with
This serves as a basic guideline for
and personal recommendations of the
the spinal column straight and the
training at home and includes several
lecturer. These courses mainly consist
forearms and hands fully supported.
tests for self-evaluation.
of basic exercises and cover topics
An adjustable chair, preferably with
such as how to pick up the needles, tie
wheels is recommended for the surgeon
After the corresponding training in
Figure 4.24a Folded cloth rolls on the patient‘s shoul-
Figure 4.24b Clinical situation with a sterile
the knots and suture under the OPMI.
who should place him/herself in the
the lab and before starting with the
ders provide an excellent hand support to avoid an
drape covering the hand rests and the face of
Usually, after the course the student is
most comfortable position. Tremor
first microsurgeries on the patient,
unfavourable tremor
the patient
abandoned to his fate.
varies with individuals and even in the
the trainee attends a second course
same individual it varies under different
that lasts one day. It is the aim of the
This is somewhat surprising as most
conditions. In some people, coffee, tea
course to control the learned hand and
courses last only one or two days,
or alcohol may increase the tremor; in
finger movements for their correctness
and just communicating the message
others, emotions, physical exercise or
and to instruct the clinician about the
is simply not enough! No matter how
the carrying of heavy weights.
ergonomic aspects that may facilitate
one’s life in clinical practice. These
During this phase an expert can just
deal with difficult situations. For that
practise and a special kind of practise
During the basic course a number of
include good hand support during
support with advice or recommendations
reason, after several years of clinical
is necessary for real understanding.
exercises are shown and practised.
microsurgical interventions, which
while the new treatment team forms by
practice, and to become an expert, the
This is no drawback, since many people
These are the same for all the different
can easily be achieved by positioning
itself. Following the learning curve and
microsurgeon may attend a third course
currently invest large amounts of motor
microsurgical specialties. The exercises
folded cloth rolls on the shoulders of
acquiring expertise, the apprentice gains
which is focused on specific exercises
skill practise time with no noticeable
should be adjusted individually
the patient before placing the sterile
proficiency. The team is now qualified
at the highest level of difficulties. Such
depending on the progress of each
drape (Figure 4.24a/Figure 4.24b). After
to manage well-known procedures
a course can just present the suitable
single participant. This guarantees the
this second instruction, the trainee
successfully under the OPMI without
exercises and provide the participants
We recommend a three step training
best learning effect. The initial training
is provided with all the necessary
any increase in duration. Intuitively, one
with the appropriate training models.
programme: In the first course, the
lasts two days and the models used are
theoretical information and manual
might suppose that practise pays off by
We are convinced that even a master in
trainee is initiated into the world of
mainly two dimensional ones.
skills to start with the first surgical
making movements increasingly more
periodontal microsurgery must undergo
microdentistry. Basic aspects such as
The third day of the basic course is
interventions, thus turning into an
precise as time passes by. That, however,
lab training from time to time and that
positioning for an ergonomic posture
dedicated to the specific periodontal
turns out to be a terrible mistake,
the lifetime training is a prerequisite to
and how to reduce natural hand tremor
and peri-implant exercises. These are
because the hand needs a new, more
constantly improve manual skills.
are taught. The latter is of the utmost
performed on models which mimic the
In the following period, the young
difficult task as a stimulus for further
importance as even normal tremor
restricted access area of the oral cavity,
microsurgical team must acquire clinical
improvement. In other words, getting
of the fingertips with excursions of a
the depth of the working field from the
routine and eliminate small errors.
better means improving one’s ability to
sincere the inquiry, a great deal of
4 OPMI in periodontology and implantology
Which are the most common errors made in the use
of the OPMI in surgical practice?
The three most common errors in the
High magnification
Changing techniques too rapidly
Lack of Practise
use of the OPMI are:
There is a tendency to use magnification
It may take six months or more
One unfortunate aspect in the use of the
Working with high magnification (12-
To acquire expertise in periodontal
1) using magnification that is
that is too high. One of the basic
for surgeons to be familiar with
OPMI is the failure to define its purpose
20x) the surgeon has to adjust to being
and peri-implant microsurgery, correct
principles of optics is the higher the
magnification of 12x, which usually is
clearly. Many scientific publications
a “prisoner” within a narrow field of
implementation of the exercises is more
too high
magnification, the narrower the field
the maximum used in plastic periodontal
on the use of the OPMI in periodontal
view. A new co-ordination has to be
important than time exposure (further
2) changing techniques too rapidly of view and the smaller its depth.
and implant surgery. A point of
and implant surgery emphasize new
sought between the surgeon’s eyes and
information: www.swiss-perio.com).
This concept is important because
diminishing returns will eventually be
techniques or technological advances,
hands – an adjustment which can come
3) lack of practise
high magnification causes surgery to
reached at the point of magnification
some of which are mainly for research
after much regular practice with simple
become more difficult, especially when
where the advantages of magnification
while others are so sophisticated that
surgical procedures only. If periodontal
it involves considerable movement. In
are outweighed by the disadvantages of
they are beyond the scope of most
surgeons say that they use the OPMI
these circumstances low magnification
a narrower field of view.
clinicians in practice.
only for difficult procedures, such as
guided tissue regeneration or recession
of 4x to 7x should be used. On the
other hand, higher magnification of 10x
There has thus been a consistent
coverage, it is likely that they have not
to 15x may be useful when dissecting
failure on the part of microsurgeons
adjusted to the OPMI. The same applies
within a small area requiring less
to stress the advantage of the OPMI.
if their operating time is significantly
movement, e.g. in papilla preservation
The OPMI is not only useful in research
increased or if they are not using the
techniques (Figure 1). In general, the
and for periodontal specialists, but
OPMI for all their surgeries, at the least
magnification should be chosen to allow
also helps a general practitioner to
those that do not require positional
the surgeons to operate with ease and
perform conventional periodontal and
without increasing their usual operating
peri-implant operations with greater
time required for a particular surgical
precision and accuracy. It follows that
Once the periodontal surgeons are able
procedure. Surgical time does not have
with the use of the OPMI, surgeons do
to do more difficult procedures and
to be increased once the surgeon has
not need to change their techniques
suture the wounds with very fine suture
adapted fully to the OPMI
necessarily, but should continue
materials (8-0, 9-0, 10-0) as a matter
The more experienced and skilled the
with those with which they are most
of routine, the standard of their basic
surgeons are with the OPMI, the higher
familiar. Changing techniques should
surgeries will also improve even if these
the magnification they can use with
be deliberately resisted until the initial
are performed with lower magnification.
adjustment difficulties have been
However, this progress can only be
attained with regular practise, which
seems to be one of the key factors in
becoming an experienced microsurgeon.
4 OPMI in periodontology and implantology
JOURNAL OF SURGERY 157: 241-242.
18: 237-250.
SURGERY 88: 658-664.
DENTISTRY 18: 449-454.
GIE 220: 323-333.
NORTH AMERICA 24: 767-781.
GERY. PERIODONTOLOGY 2000 11: 58-64.
SCANDINAVICA 143: 71-73.
ORAL SURGERY 36: 710-712.
JOURNAL OF SURGERY 157: 334-339.
RESEARCH 19: 314-319.
FÜR ZAHNMEDIZIN 114:890-896.
OF SURGERY 62: 952-955.
Restorative and
prosthodontic Dentistry
Author: Prof. Dr. Claudia Cia Worschech
Dr. Maxim Stosek
135 Why use the surgical microscope in restorative and
prosthodontic dentistry?
136 Prevention and diagnosis
137 Bacterial plaque
142 Fractured line – “cracks”
148 Preparation control
150 Matrix adaptation
153 Rubber dam applications in
anterior and posterior areas
154 Cervical lesions
156 Finishing and polishing
160 Possibilities for analyzing
the surgical field at different
164 Replacements – avoiding wear
166 The Tunnel preparation technique
168 Indirect restorations
Excellence in operative
and prosthetic dentistry with
regard to communication
with patients
5 Restorative and prosthodontics
Why use the OPMI
in Restorative and Prosthetic Dentistry?
This is one of the first questions asked by the dentists who are
The OPMI can be used for the whole spectrum of
not endodontists.
restorative procedures. Nowadays, the OPMI is an
“innovative” way to see and to do dentistry. It enhances
Modern dentistry is based on precision, and precision is an
the quality of the treatment procedure by permitting
absolute must to achieve high quality standards. Why was the
enhanced viewing of the surgical field thanks to the
use of the OPMI use in dentistry limited to the endodontic
quality, direction and intensity of the light as well as
specialty for many years? No other specialty has made
the magnification process. It is much easier to achieve
such intensive use of the OPMI as this branch of dentistry.
excellent results if the surgical area is clear. The current
However some form of magnification is indicated in all fields
treatment philosophy is to prevent and detect dental
of dentistry and should be utilized by all dentists, in all areas.
disease at the earliest stage in order to avoid invasive
All restorative procedures have become more complex, more
sophisticated and require more focus and attention. New
materials and techniques have been developed in recent years
With the current understanding of the nature of dental
and are continuing to improve on a daily basis. In conjunction
disease and its process, the treatment philosophy is now
with the development of new materials and techniques
changing to a more conservative approach, and the
there has been a massive incorporation of technology in the
concept of minimal intervention is gaining popularity in
modern dentistry throughout the world. When intervention
is indicated, the less invasive techniques such as preventive
Dentistry today demands the intensive utilization of computers
resin restoration and minimal cavity preparation are
and many other new technologies to aid the management of
utilized. Early diagnosis can allow minimally invasive
all the clinical information, digital documentation and record-
treatments to be performed, thus preserving tooth
keeping generated during the diagnosis and execution of
structure. In the long term, this conservative approach
clinical cases. As a direct consequence of all this technological
should lead to fewer complications such as tooth fracture
development and the incorporation of new materials and
and pulpitis.
techniques, dentistry today demands a multidisciplinary
approach in contrast to the unilateral perspective of the
Besides caries detection and the minimally invasive
past. Different treatment modalities can be presented and
approach using resin or other kinds of materials such
performed for the resolution of one specific clinical situation
as ionomers, many points are important to allow the
due to the many valuable treatment options available.
maximum longevity of the restorations. Direct or indirect
and marginal integrity is the first point to be analyzed
for measuring this success. If margins display gaps and
excessive material, longevity could be affected due to
microleakage. During this chapter we will show you how
you can view every step in operative dentistry and
prosthodontics and show you that magnification is the way
Figure 5.1
to the future.
5 Restorative and prosthodontics
Prevention and diagnosis
Bacterial plaque
Careful examination and correct
diagnosis are the prerequisite of any
dental professional. This requires clear
visualization of the both hard and soft
tissues. The OPMI is very helpful in many
different specialties including restorative
dentistry and prosthodontics.
Figures 5.1 to 5.8 illustrate how every
detail becomes very sharp and clear.
Figure 5.2: Plaque in the labial area.
Many imperfect surfaces provide a
Achieving a smooth tooth restoration
favorable site for residue and plaque
interface clinically to aid the cooperative
deposition. This process promotes the
motivated patient in biofilm removal
development of caries and periodontal
is an essential prerequisite to prevent
diseases. Imperfect surfaces like rough
further secondary caries and improve
or overcontoured surfaces can shorten
the longevity of all restorations.
the longevity of direct or indirect
restorations. The cavity preparations,
restorative procedures and finishing
process adopted are considered “key
factors” for the long-term success and
aesthetic outcomes for all restorations.
5 Restorative and prosthodontics
Figure 5.2: Occlusal caries viewed at high
magnification in lower molar
Figure 5.3: Approximal and secondary caries
Figure 5.4: Approximal caries on distal wall,
first upper molar plaque accumulation
Figure 5.5: Caries opening
Figure 5.6: After the caries removal
and matrix adaptation
5 Restorative and prosthodontics
Figure 8a, 8b,8c: Non-caries stain at different
magnifications ( low, medium and high)
Figure 5.8a
Figure 5.8b
Figure 5.8c
5 Restorative and prosthodontics
Fractured line – “cracks”
Figure 5.9a
Figure 5.9b
Clinicians have had the ability to observe
Without the information provided by
cracks under extreme magnification for
microscopic inspection at high power,
nearly a decade. Patterns have become
many teeth with structurally significant
clear that can lead to appropriate
cracks would have been treated only
treatment prior to symptoms or before
when they were symptomatic. This can
devastation of tooth structure occurs.
result in more complicated, involved
Conversely, many cracks are not
treatment, or even a catastrophic event
structural and can lead to misdiagnosis
that leads to tooth loss.
and overtreatment.
Most of these superficial fractures
Methodical microscopic examination,
are relatively undetectable without
an understanding of crack progression,
magnification, but when viewed under
and an appreciation of the types of
high power, hairline cracks appear as
cracks will guide the dentist to making
appropriate decisions. Teeth can have
structural cracks at various stages. To
date, diagnosis and treatment have very
often been made at a late stage of the
Figures 5.9a, 5.9b and 5.9c:
Fractured premolar viewed
at low, medium and high
Figure 5.9c
5 Restorative and prosthodontics
Figure 5.10 Fractured premolar
Many fractures like this are not
observed without high quality light and
Cracks can occur in teeth restored
with amalgam due to the physical and
chemical properties of the restorative
material (setting expansion, corrosion,
coefficient of thermal expansion etc).
The forces on the remaining tooth
structure can cause deflection of the
cusps, cracking and ultimately fracture
of the cusps.
Figure 5.11 Molar presenting crack
under the cusp (low magnification;
medium magnification and high
5 Restorative and prosthodontics
Figure 5.13: This image demonstrates the ability of the OPMI to
Figure 5.14: Cracked tooth syndrome.
show a verical root fracture
Note the enamel crack disto-palatally
Figures 5.15a Mesio-distal crack viewed with the aid of the operating light of
Figure 5.15b The same crack viewed using
the OPMI
Figure 5.12 Fracture line in the floor of the cavity
and under the cusp visible in high magnification.
5 Restorative and prosthodontics
Preparation control
Figures 5.16a
Figures 5.16b
Figure 5.17a Without OPMI
Figures 5.16a and 5.16b: Note recurrent caries
reaching the dento-enamel junction and leakage
around the restoration in the adjacent tooth.
Magnification is really useful to avoid
unnecessary destruction of healthy
dental tissue because it is possible to see
the boundaries between the restorative
material and dental tissue in great detail.
Without magnification, this cannot
be seen with the same clarity leading to
more extensive tooth preparation, loss
of healthy tissue and potential damage
to the pulp
Preparation for indirect restorations
are vastly enhanced with the aid of
the OPMI as prepared surfaces can be
finished with greater accuracy leading
to better fitting restorations.
Figure 5.17b With OPMI
5 Restorative and prosthodontics
Matrix adaptation
Figure 5.19a: situation before the
Figure 5.19b: subgingival calculus
Figure 5.19c: Correct matrix adaption
Figure 5.19d: Correct right matrix
matrix placement. Note the small
obstructing the correct placement of
but note the decalcified enamel at
adaptation, after the final enamel
space between the rubber dam
the matrix
the marginal line
slightly not adapted to the mesial
wall of the cavity
When direct restorations are made,
The simple fact of working with cavities
special attention needs to be
on opposite walls from dissimilar
paid to margins, especially dentine
tissues like dentine and enamel creates
intrinsic problems in itself. Managing
their completely different adhesive
The biggest problems continue to be the
behavior is one aspect that should not
adequate sealing of the margins and the
be overlooked.
correct contact point, for most kinds of
restorations and independently of the
Any excess or roughness of restorative
materials used.
material should be avoided. Plaque
(See Figures 5.18a - 5.19d).
retention, gingival inflammation, and
occurrence of carious lesions represent
Eliminating or reducing the gap
not only a failure of the restoration but
formation on the gingival floor is a
also a creation of new problems to the
patient. Techniques with minimum need
of finishing and polishing are ideal, but
properly contoured restorations are
seldom achieved without the need to
remove excess of material.
Figures 5.18a
and 5.18b: Note
the image on the
left where the
matrix band is not
Figure 5.18a
Figure 5.18b
5 Restorative and prosthodontics
Rubber dam applications
in anterior and posterior areas
Figure 5.20: Note the
poor cervical adaptation
of the matrix and
incorrectly shaped
contact point
Figure 5.23
Figure 5.24
Figures 5.23 and 5.24 the correct insertion of
The cervical adaptation of the
Another critical factor associated with
restoration is important. This defect
restorations in general and with indirect
can be illustrated with the scanning
aesthetics restorations in particular is
electron microscope image (fig 5.21),
periodontal health, and for longevity of
which shows us the imperfection on the
restorations the precision of the margins
approximal wall. A gap often results if
at the periodontal-restorative interface
Rubber dam can be used to achieve
the matrix is not correctly adapted.
is required. Improper margins can cause
more effective isolation of the surgical
Clinically, we deduce why the
overhangs and over-contouring that may
field or for better insertion of a
restoration has failed. Because the
ultimately result in caries, periodontal
interface between the tooth and the
inflammation and breakdown, and
Figure 5.21: Through a scanning electron
composite resin is not sealed, a gap
compromised aesthetics. In order to
microscope it is possible to see a gap between the
emerges and the patient may feel pain
prevent pathology at the restorative
or sensitivity. Sometimes the restoration
tooth interface, each phase of the
has to be replaced.
aesthetic treatment must be performed
rubber dam applications. In fact, the OPMI can be
used during all procedures related to restorative
and prosthodontics
retraction cord, thus avoiding bleeding.
Figures 5.23 and 5.24.
resin restoration and the tooth surface, probably
because of incorrect matrix position and poor
adaptation of resin against the matrix
with precision and care.
Cervical enamel has an important
impact on the performance of Class II
composite restorations by improving
strength and adhesive properties of the
Figure 5.22: This image shows current lack of
adaptation of resin restoration in mesial surface
of molar
Figure 5.25 Note the imperfect application of the
Figure 5.26
rubber dam, clearly visible under magnification
5 Restorative and prosthodontics
Cervical lesion
Figure 5.28
Figure 5.29
Figure 5.30
Figure 5.26
Cervical lesion can be viewed perfectly
Proper rubber dam isolation is very
Figures 5.26 - 5.31: Non-carious lesions
through the OPMI - from minimal to
difficult, sometimes impossible,
were viewed at low, medium and high
pronounced lesions involving pulp
when lesions extend aproximally or
inflammation. Attention should be given
subgingivally. Sometimes part of the
cervical surface. This calculus should
to non-carious lesions in cervical areas.
structure cannot be isolated and the
be removed before the resin insertion.
Cervical restorations need to be very
dam promotes accumulation of the
well adapted because they can lead to
restorative material. Access is also
an increase in the level of plaque,
limited, causing problems related to
potentially resulting in secondary caries
insertion of the restoration. When
and periodontal disease.
adequate rubber dam isolation is not
possible, an alternative method of
isolation (i.e. cotton rolls) has to be
magnifications. Note the presence
of calculus around the lesion on the
Magnification was essential to allow
correct viewing and removal
Figure 5.27
Figure 5.31
employed. See Figures 5.26 - 5.31
5 Restorative and prosthodontics
Finishing and polishing
Figure 5.32a
Figures 5.35a and 5.35b: This clinical case
exemplifies the resin restoration which was
polished without an OPMI
Figure 5.32b
Figure 5.33
Figure 5.35a
Figure 5.32a - 5.32b: These images showed direct
restorations after polishing, without OPMI usage.
Note that a certain amount of resin was kept
over the surface, toughening the gingival margin.
This could not be seen without magnification, but
was clearly visible under the OPMI
Figure 5.34 Through the scanning electron microscope this
excess of material is viewed easily and concur with the images
provide through the OPMI
The clinical case below showed how
or when dental floss remains jammed
to improve the appearance and
important it is to remove and clean
between the teeth. Here, the OPMI can
health aspects. In many cases, these
residues around composite resins.
help dentists and technicians to achieve
restorations have to be either replaced,
Gingival irritation and marginal tissue
precision in restoration margins of direct
resulting in the potential further
inflammation could be avoided using
or indirect restorations.
destruction of healthy tissues,
or adjusted to improve the existing
simple procedures and thanks to the
high-precision view of the surgical field
When adhesive material accumulates
result. Adjustment can be very
enjoyed by the dentist.
near gingival tissue, inflammation may
challenging especially in areas where
result, and pain and discomfort could
the access is difficult. A good gingival
Most of the time, patients are not as
require replacement of the restoration.
displacement and the use of enhancing
discriminating in their ability to
Aesthetic restorations can be harmful
optical devices are indicated. See Figures
identify small color differences between
due to imperfect finishing of margins,
5.32 - 5.41 for images showing perfect
composite restoration and tooth as
resulting in pigment retention and an
and imperfect polishing, reflecting light
dental professionals. On the other hand,
unattractive appearance. In most clinical
zone, etc.
all patients notice when restorations
cases of this kind, these restorations
are not accurate, when there is a gap,
have to be replaced in an attempt
Figure 5.35b
5 Restorative and prosthodontics
Figure 5.36
Figure 5.37
Figure 5.39
Figure 5.40
Figures 5.36 and 5.37: At high magnification
Figures 5.39 and 5.40: Close-up of texture and
you can see details of irregular surfaces after
polishing on the left. On the right you can see
polishing (left). The image through a scanning
the image captured though a scanning electron
electron microscope shows the rough surface
on an incisal area
Figures 38a and 38b: Restoration was
Figures 5.41a and 5.41b: Note the polishing after
re-polished. Note the much smoother
bracket removal. All resin used to bracket fixation
was removed without damage to the enamel
Figure 5.38a
Figure 5.41a
Figure 5.38b
Figure 5.41b
5 Restorative and prosthodontics
Possibilities for analyzing the surgical field
at different magnifications
Figure 5.42a
Figure 5.42b
Working with the OPMI provides
many possibilities for viewing the
surgical field. This is one of the most
important advantages offered by OPMIs,
besides excellent quality of light. See
Figures 5.42a - 5.42c. In restorative
and prosthodontic dentistry it is very
important because the dentist can see
much more than the tooth that is being
Figures 5.42a, 5.42b and 5.42c:
Surgical field at low, medium and
high magnifications
Figure 5.42c
5 Restorative and prosthodontics
Figure 5.43b
Figure 5.43a
Figures 5.43a, 5.43b and 5.43c:
Surgical field at low, medium and high
Figure 5.43c
5 Restorative and prosthodontics
Replacements - avoiding impairment
Figure 5.44 - 5.46: captured with an OPMI and
scanning electron microscope exemplify the most
common occurrence during restoration replacement
without any kind of magnification
Figure 5.45
Figure 5.46
When we replace restorations (aesthetic
Improved lighting coupled with
Adhesive restoration eliminates the
or non-aesthetic) due to a recurrent
magnification provide a clear distinction
need for more extensive and retentive
carious lesion, or because of superficial
between surfaces that may look similar
preparations. Enamel - like composites
or intrinsic discolorations of resin which
in color or texture under traditional
offer long-lasting replacement of tooth
damage the aesthetic restoration’s
working conditions, but look very
structure with minimum requirements
quality, healthy tooth material is
different under the OPMI. Decay,
for restorative bulk; little or no healthy
often also removed at the same time.
dentine, enamel, composite, and
tooth material needs to be removed
Recognizing the limits between teeth
porcelain are easily discernible from
simply to allow for an adequate thickness
and restorations, seeing these structures
one another and can be viewed with
of the filling materials. Aesthetic and
with magnification and high quality
unprecedented detail under the scrutiny
cosmetic procedures calling for invisible
light, means greater preservation of
of the OPMI.
margins and tooth / restorative interface
tooth tissue. (Figures 5.44 - 5.46.)
The images above exemplify how an
transitions are far easier and less stressful
amount of resin that can remain around
when size enhanced visualization is
the cavity preparation if dentists cannot
see the boundaries of the preparation
in detail. Conversely, teeth may be over
prepared by the removal of healthy
tooth tissue at the margins of the
The replacement of an amalgam or
aesthetic restoration often leads to ever
larger restorations that have shorter life
spans than their predecessors, and the
replacement procedures themselves may
often cause damage to adjacent healthy
Figure 5.44
5 Restorative and prosthodontics
The Tunnel preparation technique
Figure 5.47a Initial access to the decay
Figure 5.47b Initial view of the tunnel preparation and removal of decay
Figure 5.47c Detailed view of the tunnel preparation and inspection
Figure 5.47d Inserted matrix to seal the tunnel
of the marginal ridge for cracks
Figure 5.47e 1st layer of flowable composite to seal the tunnel under visual
Figure 5.47f Completed restoration
Figure 5.47g Detailed view of the finished restoration and the marginal ridge
The Tunnel preparation technique is a method in which
Contraindicaton of this technique is where the marginal
approximal demineralised enamel is partially or completely
approximal caries is accessed and prepared through the
ridge is undermined with decay or demonstrates cracks. It is
removed and then smoothed.
occlusal surface preserving the marginal ridge intact with
advisable to maintain at least 2.5 mm of tooth tissue between
occlusal centric contacts. This method allows less removal of
the crest of the marginal ridge and the cavity margin.
The failure risks include fracture of the marginal ridge,
enamel and dentine compared to a traditional class II cavity.
The efficacy of caries removal is the main problem. It is
incomplete removal of caries and secondary caries.
This minimally invasive approch to approximal decay is
limited by the size of the occlusal access – it may be too
These risks are reduced by the control given by the OPMI.
indicated in cases of approximal lesions and intact occlusal
small to see all the undermined areas. Combination of higher
surface, or a pre-existing occlusal restoration which is removed
magnification, caries detector dye and transillumination
to gain the access. In the teeth with an intact occlusal surface
techniques improves the effectiveness of caries removal.
the ideal position of entry is the fossa next to the marginal
Cavity design varies from the tunnel in which the approximal
enamel is maintained to a partial or total tunnel where
Figure 5.47h After polishing the restoration and rewetting of the tooth
control and transformation of the class II cavity into a class I cavity
5 Restorative and prosthodontics
Indirect restorations
Figure 5.48
Figure 5.49
Figures 5.48 and 5.49: Note the
excess of resin cement, after
cementation. This kind of material
can damage the surrounding soft
tissue and should therefore be
Figures 5.50 and 5.51 Note the
exact definition of preparation on
the cervical area through the use of
magnification. At low magnification
it is also possible to check the
smoothness of preparation in each
tooth involved in the restorative
Figure 5.50
Figure 5.51
Note the excess of cement in the
In order to avoid overhangs during
boundary between the tooth and
ceramic bonding, marginal adjustments
the ceramic restoration. Without any
are made using small burs and rubbers.
magnification this is difficult to see
The smoother and more regular they
and remove adequately. These OPMI
are, the better the adaptation of the
images show us the exact point where
indirect restoration. See Figures 5.50
finishing and polishing must be done.
and 5.51.
See Figures 5.48 - 5.49.
Figure 5.52: Thanks to the high
magnification and clear light
Other important considerations include
provided by the OPMI, it is possible
the correct removal of the retraction
to see residues of the retractor cord
cord after cementation of laminates.
used during cementation procedure.
These residues must be removed to
Parts of the cord often remain in the
prevent plaque retention and gingival
cervical area. If the dentist does not use
either magnification or clear light, these
residues cannot be seen(Figure 5.52).
5 Restorative and prosthodontics
Figure 5.53a
Figure 5.53b
Figure 5.55: Note the accurate
impression of the preparation
Figure 5.54a
Figure 5.54b
Figure 5.56a
The aim of clinicians and technicians.
is to achieve excellent margins and
perfect adaptation. Clear visibility of the
Another important aspect concerning
Figures 5.53a and 5.53b: Note the perfect adapta-
indirect restorations is the visualization
tion of ceramic microlaminates when treatment
of impressions, and not only the
surgical field and high magnification
is carried out with the aid of the operating micro-
visualization of the impression material,
are very important to reach that goal.
scope... The ceramic microlaminates were made by
but also the adaptation of the material
If excellence is achieved the results are
Marcos Celestrino TPD – BRAZIL
highly satisfying for both the patient
and the clinician and also longlasting.
See images 5.53a, 5.53b and 5.54a and
to the teeth. See Figures 5.55, 5.56a
and 5.56b.
Figures 5.54a and 5.54b: Note the excellent tissue
response to the ceramic microlaminates after 5
years in the mouth.
Figure 5.56b
Figures 5.56a and 5.56b: There is perfect adaptation of the coping to the papilla margin; however,
there is incorrect adaptation through the cervical
5 Restorative and prosthodontics
Figure 5.57
Figure 5.58
Figure 5.59
Figure 5.60
Restorative dentistry under the
microscope requires modified
instrumentation to take full advantage
of this treatment modality. Microburs, micro-mirrors and flexible mirrors
are available for this type of high
precision clinical work. The high quality
illumination only 200-300 mm from the
mouth provides vastly superior light than
the overhead operating light used by
most clinicians. See Figures 5.57, 5.58,
5.59, 5.60 and 5.61.
Figure 5.61
Figures 5.57 - 5.61: Note the differences between these instruments.
Working under magnification requires delicate instruments, small
mirrors, small burs and brushes.
5 Restorative and prosthodontics
Excellence in operative and prosthodontic dentistry
with regard to communication with patients
Figure 64: Dentist and assistant working in
perfect harmony using the OPMI and shooting
and recording images at the same time
Figure 5.62 The use of video and still photography enable documentation of clinical cases. The
images can be used to explain findings to patients
in perfect detail
The ease of communication with the
patient is, without doubt, another
Figure 5.63
Figure 5.64
Figure 5.65
Figure 5.66
great benefit inherent in the use of
the OPMI. All clinical images can be
recorded by cameras or camcorders
and all the details of each clinical case
can be shown at the same time for the
patient. The OPMI accessories provide
exact recording of the images, with high
quality and sharpness.
See Figures 5.62 - 5.66.
5 Restorative and prosthodontics
WORSCHECH CC et al: Micro-operative dentistry:
FREEDMAN G, GOLDSTEP F, SEIF T: Ultraconservative
N – SPEAR F, HOLLOWAY J: Which all-ceramic
profissional com o paciente. R.Dental Press Estética
D K Ratledge, E A M Kidd & E T Treasure- The tunnel
Why do it? QDT 2007, 199-205
resin restorations “watch and wait” is not
system is optimal for anterior esthetics? J. Am Dent
– Maringá, v.4, n.3, p.24-33, julho/agost/set 2007
restoration, British Dental Journal 193, (2002)
acceptable treatment. Dentistry Today,
Assoc, vol 139, No suppl_4, 19S-24S, 2008)
Diagnosis of secondary caries in esthetic restoraX-ray beam. Braz Dent J. 2011;22(2): 129-33
WORSCHECH CC, MURGEL CAF: Micro-odontologia:
Strand GV, Tveit AB Effectivenesss of caries removal
HORN HR: A new lamination: porcelain bonded to
visão e precisão em tempo real. Maringá-Dental
by the partial tunnel preparation method.
enamel. NY State Dent J 1983; 49(6): 401-403
Press Editora, 2008, 482p
Scand J Dent Res 1993; 101: 270–273.
SIMONSEN RJ, CALAMIA JR: Tensile bond strengths
Pyk N, Mejàre I Tunnel restorations. Influence of
of etched porcelain. Abstract 1099. J.Dent Res,
luting composite srinkage and thermal loads on the
some of the clinical variables on the success rate.
stress distribution in porcelain laminate veneers.
Acta Odont Scand 1999; 57: 149–154.
january 2000
tions: influence of the incidence vertical angle of
FRIEDMAN M, MORA A, SCHMIDT R. Microscopeassisted precision dentistry. Compend Contin Educ
Dent 1999; 20:723–735
FM. Braz Oral Res, 2010 Jan-Mar; 24(1): 102-7
Microscope-assisted precision (MAP) dentistry.
SHEETS CG: The periodontal-restorative interface:
A challenge for new knowledge.
enhancement through magnification. Pract perio-
J Calif Dent Assoc 1998;26:900–905
dont Aesthet Dent 1999; 11(8):
FREEDMAN G, GOLDSTEP F, SEIF T: Ultraconservative
J. Prosth Dent 1999, 81: 335-344
CALAMIA JR: Etched porcelain facial venners :
KINA S, BRUGUERA A: Invisível: Restaurações
clinical evidence. N Y J Dent 1983; 53(6): 255-259
estéticas cerâmicas. Maringá – Dental Press
Editora, 2007, 420p)
resin restorations “watch and wait” is not acceptaFRIEDMAN M, MORA A, SCHMIDT R
ble treatment. Dentistry Today, january 2000
Microscope-assisted precision dentistry. Compend
Contin Educ Dent 1999; 20:723–735
Knight GM The tunnel restoration. Dent Outlook
a new treatment modality based on scientific and
1984; 10: 53–57
Nicolaisen S, von der Fehr FR, Lunder N, Thomsen I.
Performance of tunnel restorations at 3-6 years.
layer as a dentin-bonding mechanism. J Esthet Dent
1991; 3 (4): 133-138
Clinical performance of novel design porcelain
J Dent 2000; 28: 383-7.
veneers for the recovery of coronal volume and
Kinomoto Y, Inoue Y, Ebisu S. A two-year
on microscopic evaluation. J. Esthet Restor Dent
POSPIECH P: All-ceramic crowns : bonding or
length. Int J. Periodontics Restorative. Dent 2000;
comparison of resin-based composite tunnel and
Minimal intervention concept: a new paradigm for
cementing? Clin Oral Investig 2002; 6(4): 189-197
20: 441-457
class ii restorations in a randomized controlled trial.
GARCIA A: Dental magnification: a clear view of the
N – SPEAR F, HOLLOWAY J: Which all-ceramic
LESAGE B: Finishing and Polishing criteria for mini-
present and close-up view of the future. Compendi-
system is optimal for anterior esthetics? J. Am Dent
mally invasive composite restorations. Gen Dent.
um, June 2005, 459-453
Assoc, vol 139, No suppl_4, 19S-24S, 2008)
2011 Nov-Dec; 59 (6): 422-8; quiz 429-30
JOHANSSON AK. Class II composite restorations:
ARENS DE: Introduction to magnification in endo-
SIMON H, MAGNE P: Clinically based diagnostic
importance of cervical enamel in vitro
dontics. J. Esthet Restor Dent 15: 426-439, 2003
wax up for optimal esthetics: the diagnostic mock
and restorative dentistry: old and new risks. Ned
up. J. Calif Dent Assoc, 2008, May; 36(5): 355-62
Tijdschr Tandheelkc, 2009 Jun; 116 (6): 291-7
agnosis of early enamel and dentinal cracks based
operative dentistry. J.Investig Clin Dent 2012 Aug;
3(3): 167-175. doi: 10.111/j
2041-1626.2012.00117.x.Epud 2012 Feb 8.
Am J Dent 2004; 17: 253-6.
SHEETS CG: The periodontal-restorative interface:
RAGAIN J, JOHNSTON WM: Minimum color differen-
enhancement through magnification. Pract perio-
ces for discriminating mismatch between composite
dont Aesthet Dent 1999; 11(8):925-931
and tooth color. J. Esthet Restor Dent 13: 41-48,
The importance of laboratory communication in
modern dental practice: stone models without
Validity of caries detection on occlusal surfaces and
faces. Pract Periodontics Aesthet Dent, 1999,
treatment decisions based on results from multiple
NOV-DEC; 1125-32; quiz 1134
caries detection methods. EUR J Oral Sci. 2009 Feb;
BAUMANN RR.: How may the dentist benefit
of noncarious cervical lesions: when, why , and
from the operating microscope? Quintessence Int
how. Int J Dent 2012;2012: 687058. Published on-
117 (1): 51-7.
WORSCHECH CC, Microdentistry: A Path to
excellence. QDT 2008, 179-187
line2011 December 18.doi: 10.1155/2012/687058
SWENSON E, HENNESSY B: Detection of occlusal
FRIEDMAN MJ, LANDESMAN HM: Microscope-assis-
Microscópio cirurgico: lanueva frontera de la
WORSCHECH CC: Microscopia Operatoria na
carious lesions: an in vitro comparison of clinicians`
ted precision (MAP) dentistry. A challenge for new
Odontología clínica Del siglo. Fola/
Medicina Dentária. Aesthetic&Implant
diagnostic abilities at varying levels of experience
knowledge. J Calif Dent Assoc 1998;26:900–905
Dentistry Out. Nov. Dez. 2008
WORSCHECH CC: Replacement of esthetic restora-
TERRY DA; GELLER W: Selection defines design.
WORSCHECH CC: Microscopia Operatória na
approximal carious lesions. J Am Dent Ass 1990;
tions: Can we see the limits? R. Dental Press Estet,
J. Esthet Restor Dent, 2004; 16(4): 213-25;
Odontologia: Como a magnificação pode
120: 37–40.
Maringá, v.3, n.4, p.77-90, out/Nov/dez. 2006
discussion 226
aprimorar a habilidade técnica e a comunicação do
Hunt PR Microconservative restorations for
Author: Oscar Freiherr von Stetten
181 Why?
186 Practical advice
6 Documentation
Why documentation?
The increasing use of magnifying devices in the dentist’s
practice is also leading to a need to document the diagnosis
and treatment, whether for forensic purposes, for the
dentist’s own documentation needs, patient education,
training or case presentations.
Figure 6.1
6 Documentation
Figure 6.3
The optical beam path contains a beam
different sizes. When purchasing, it
to exchange the camera hardware
splitter that routes a certain percentage
is important not to simply choose the
without any immediate need for a new
of the incident light to the camera by
model with the lowest price – this
tube. The prefabricated optics of the
means of prismatic lenses with defined
reflects the optical quality and of the
consumer grade cameras are eliminated,
transmission properties.
camera lens – and ensure that a filter
resulting in considerably more light and
thread is present.
better optics. In addition, these devices
have been optimized to meet the needs
Figure 6.2
The biggest benefit of the video
A further benefit of the video solution
of their intended application, i.e. certain
solution is that very little light is needed
is the weight. The less weight there
parameters have been adapted to usage
(approximately 10%).
is on the OPMI head, the less weight
on the OPMI.
also has to be moved when setting the
Various manufacturers offer different
OPMI. In addition, the camera hardware
should first ask themselves for what
In addition, video solutions may be very
OPMI, making it more stable and less
One drawback of video systems is the
documentation solutions. Unfortunately,
used does not play a really decisive
purpose the images or videos are to
suitable for generating high-quality
sensitive to vibrations or imbalance.
still enormous file sizes they involve.
it is often the case that the dentist does
role, despite the many beliefs to the
be utilized and then make a decision in
photos if high-quality cameras are used
The other class of video cameras with
Considerable time and skill is also
not realize until after several weeks of
contrary that often lead to unnecessary
favor of one particular solution.
for documentation. Consumer cameras
a separate camera head – the medical
required for the editing process,
use that the usually expensive solution
expenditure. Documentation is subject
may be interesting from the price
grade cameras – are more expensive
although a few more intuitive solutions
does not fulfill the intended purpose and
to the laws of physics that cannot be
perspective, but they have drawbacks
than consumer grade cameras, but
have already been established on the
that the quality is not of the standard
overcome. As impressively shown in
when it comes to quality. However, their
feature special benefits. One advantage
normally associated with normal
Chapter 1, the depth of field of OPMI
attachment is very simple.
of the medical grade devices is their
photography or video recordings.
optics is limited by the principles of
ZEISS has developed the FlexioMotion
standardized interface, the c-mount,
It is important to note that the
physics, as are light conduction and light
adapter for this purpose. This allows
which require smaller optics with smaller
experience gained in everyday
output. Nevertheless, it is subjective
easy, uncomplicated attachment via
focal length, which provides better
photography cannot be transferred
perception that ultimately determines
filter threads that are available in three
optical quality. This makes it possible
one-to-one to documentation with the
what technology is used. Dentists
6 Documentation
External Camera Adaptation
Recommended for full size chip cameras
• Sensor: Full size 24 x 36mm e.g. Canon EOS 5D Mark II
• Sensor APS ~15 x 22mm e.g. Canon EOS 600D
Camera chip size too small in relation
Camera chip size correct in relation to
Camera chip size too big in relation
to focal length of photo adapter
focal length of photoadapter
to focal length of adapter
Image looks “cropped“
Image has full resolution, no blackcorners
Black corners, fine structures might
not be resolved
Figure 6.4
At the IDS 2013, ZEISS presented a
desired image section has been focused
Full Frame
What light?
In addition, the mirror should be free
To compensate for this, the
device showing what such a system
sharply and at the right point.
In the past a recommendation for the
For photography, it is important that
from scratches and/or spray, but that
installation of a co-observation tube is
could look like. However, the same
As human beings tend to accommodate
use of full-frame cameras could not be
enough light intensity is installed in the
goes without saying. It is recommended
recommended to make it possible to
quality should not be expected from
with their eyes, it may well be that
justified. They were expensive, heavy
OPMI. At the moment (2013) only xenon
to have a dedicated photo mirror for
check whether what you want to image
a still frame extracted from a video
although we see the image sharply
and too complicated to use on the
can be used for photodocumentation.
this purpose.
really is in focus, or whether the image
stream as from a photo taken with
image (transmitted to the camera
LED technology is not yet advanced
enough to replace xenon.
is in focus or if corrective action has to
Fine focusing
be taken. The best way is to use the
As the depth of field range continues to
“live- view” function, which allows for a
much higher degree of focus control.
a digital single reflex camera (DSLR)
through the beam splitter) is not sharp.
Now, with the further development
camera. 2.1MP is available compared
In other words, we perform a
of the mirror-less class of camera,
to 10 MP upwards; the resolution alone
readjustment with our eyes, something
Sony offers a mirror-less full-frame
decrease as a function of the increasing
makes a direct comparison impossible.
that the camera cannot do due to the
camera system which can be fully
Mirrors play a key role in photography.
OPMI magnification, fine focusing
Nevertheless, the benefits of higher
absence of the required possibilities
recommended for the use with the
Even the highest light intensity from the
becomes necessary to obtain a “sharp”
speed combined with low image
(no objective lens with focusing). It has
OPMI. It is light weight, easy to use
illumination apparatus is worthless if the
image of the structure to be treated and
noise open up new approaches to
the further benefit that the preview
and offers some useful functions like
mirror cannot reflect enough light.
hence imaged.
image does indeed correspond to the
built-in Wi-Fi. Together with the proven
mounted on the OPMI was the Canon
Zeiss Phototube f=340 adaptor, it is
300D with 6 MP. Today entry class
possible to get high quality pictures
The first question to be asked is what
DSLRs come up with 16 MP. Even the
with ease. Due to the light weight
camera type should be selected. Should
electronics are better and faster than
and the small size of the camera body,
it be a DSLR, a compact or a mirrorless
2004, it makes no sense to get more
the manoeuverability of the OPMI
camera? As we, unlike laboratory
than 10-14 MP in terms of quality. In
is not impeded. If using the LED in
microscopy, deal with moving objects
90% of the quality regarding the picture
conjunction with the Varioscope, an
(patient movement, vibrations of the
is influenced by the optics, it makes
external documenatiaton system can
OPMI), we must accept
no sense to invest in a very expensive
not be recommended. For these cases
A live video image plays a major role in
camera, as there will be no significant
the integrated HD-Recording provides a
focusing. Only a preview monitor makes
increase in quality.
better suitability.
it possible to really see whether the
Figure 6.5
6 Documentation
Figure 6.6
Practical advice
ISO setting
“band of sharpness” is used. The art
RAW images are very big and definitely
not done regularly, allocating the right
a reliant archiving solution to hold all
In documentation with the OPMI
This is achieved indirectly through
is how to bring all important areas of
require post-processing with special
images to the right patient can become
the data for the particular patient in one
sufficient stabilization is a must. Patients’
amplification of the image signal.
the region to be documented into the
software. This means that more time
place with easy access. Without a post-
movement due to breathing, swallowing
Here, both the useful (amplified) data
image plane. The target eyepiece and
and effort is required to save the file,
and muscle tremor are an additional
and unwanted data (noise, crosstalk,
the focusing monitor are of excellent
but also for user familiarization with the
There are several Media-Workflow-
with the OPMI can easily become a time
interfering and destabilizing factors.
etc.) are amplified. This in turn leads
assistance here.
RAW workflow. The advantage of the
Software solutions available. In
consuming and frustrating task.
RAW format is the broad spectrum of
conjunction with wireless technology
processing workflow, documentation
Here it is important to achieve maximum
to digital picture images having a very
stability in the overall system comprising
grainy appearance at high ISO settings,
Remote release
editing possibilities that it offers. The
like the Eye-Fi-Card a smooth, easy
the dentist, instrument and patient. A
i.e. they display a high level of noise.
As any instability of the OPMI, combined
dynamic potential offered by the sensor
and user-friendly workflow is possible.
For the attachment of a camera, it is
with involuntary movement of the
can be utilized to the full (an important
The Recording-Solution from Zeiss
important that the adapter is computed
direct support should be sought, e.g. a
rubber dam on a tooth. It is important
Depth of field
patient, involve the risk of system
aspect), and the editing takes place
streams live video into the network
for the correct image circle. The most
that adequate stability is achieved and
The term “depth of field” is used to
tremor, any unnecessary manipulations
under the full control of the user instead
for viewing through various devices
common sensor format in the consumer
that the area to be documented must be
describe the extent that an object that
of the camera should be avoided. Only
of in the black box of the camera. Here,
such as computer, iPad or similar. The
market is currently APS-C. Full-frame
clearly visible.
can be see as “sharp” in the image
infrared or radio remote releases are
once again, it is the personal taste
software record onto shared network
cameras do not offer any real benefit for
plane. The maximum depth-of-field
suitable for this.
and requirements of the user that are
or USB devices as well as facilitate easy
OPMIs, but can be attached if desired.
transfer on still images and HD videos
Pixel size of camera
ranges are defined by the OPMI optics
Another important subject is the
(Table 1). If we bear in mind that the
sensor or pixel size, not only because
maximum magnification has a depth-
The discussion about the right file
this software is not usable with external
it indirectly influences the depth of
of-field range of only 0.9 mm, it quickly
format would appear to be endless.
Once the picture has been taken, an
documentation solutions. Depending on
field, but also because noise increases
becomes obvious that documenting at
Both have their merits, but also their
efficient workflow must be established
the country, there are many solutions
with decreasing pixel size and the light
maximum magnification does not make
to take full advantage of the modern
available on the market. As an additional
sensitivity drops. A combination would
any sense.
JPEG is small, and in most cases does
documentation systems. In 2014 it
benefit, most of the media-administering
not need any editing and is immediately
seems like an anachronism to remove
softwares are able to import literally all
be desirable: a small sensor size for the
to patient management software, but
depth of field, large pixels for detail and
Band of sharpness
available. One of its drawbacks is the
the memory card from the camera and
media, including CBCT-data With the
modern sensor and signal processing
Due to the restricted depth-of-field
tricky setting of the image parameters
wait for the computer to import the
further growth of media data available it
range of the OPMI optics, the term
and the limited editing possibilities.
images. This is time consuming and if
gets more and more important to have
Practice Management
Author: Dr. Manor Haas
The benefits of the OPMI
extend far beyond
the obvious and well-proven
clinical benefits.
192 Integration into
clinical practice
193 The OPMI
as a communication tool
Dento-legal aspects
194 Marketing
the OPMI
195 Health benefits to the dentist
196 Financials of the OPMI
7 Practice Management
The benefits of the OPMI extend far beyond the
obvious and well-proven clinical benefits.
As well as the multiple clinical benefits that have been
explained in earlier chapters, the OPMI offers enormous
potential for growth and ultimately can pay for itself many
times over.
Many of the procedures highlighted could not be performed
without the OPMI and therefore it enables the clinician
to offer many more treatments than would otherwise be
Having more control of the clinical environment can lead
to greater efficiency (i.e. reduced time looking for sclerosed
canals), less stress and more predictable outcomes.
Patients rapidly come to understand that a dentist using
the OPMI is working at the very highest standards of the
profession and with the ability to document, this greatly
increases acceptance of treatments.
Figure 7.1
7 Practice Management
Integration into clinical practice
Figure 7.2 Dentist and his assistant getting
Figure 7.3 Dentist and his assistant trained in four-handed
training in a clinical environment
The OPMI as a communication tool
Figure 7.6 The patient‘s dental
condition explained with the aid of the
OPMI and camera.
Figure 7.4 Note the low magnification, seen in the
Figure 7.5 Dental assistants who are new to
monitor, used while this dentist is in training
OPMIs are receiving instructions from experienced
The use of the image capturing
capabilities of the OPMI provides a
powerful communication tool. Whether
it is with still or video images, showing
The dentist and staff need to appreciate
When first using the OPMI, the dentist
patients the state of their oral health
Figure 7.7 This is what patients see
Figure 7.8 What patients see when
the fact that there is a learning curve
should work under low (or lower)
makes it easier for them to understand
looking through a hand-held mirror
shown an image captured with the
to using the OPMI. In turn, a little bit
magnification. As proficiency and
the problem at hand. It is easier for
of extra time should be set aside for
comfort levels improve, magnification
patients to agree to treatment when,
treatments in the initial period until they
could be increased.
for instance, they are shown a close-
Dento-legal aspects
become proficient in its use.
up of a faulty restoration margin and
A picture is worth a thousand words
Dental assistants should be trained in
are recommended to have it replaced.
and this is very significant when it
true four (or six)-handed assisting under
Acceptance of treatment would be
comes to record keeping. For instance,
the OPMI prior to the introduction of
reduced if it were only discussed
not only is it easy to diagnose hairline
the OPMI. This will help the dentist
verbally. The OPMI can therefore help
fractures, but it is also easy to record
tremendously in practising efficiently
to increase acceptance rates and
them in the patient’s chart. The more
and ergonomically.
treatment fees.
documentation, the lower the dentolegal risks to the dentist. The more
patients understand their dental
condition, the less likely they are to
misunderstand and complain.
7 Practice Management
Marketing the OPMI
The mere use of the OPMI impresses
There is no shame in educating your
patients and demonstrates the high level
patients and the general population
of treatment offered by the dentist. It
about the benefits of the OPMI and of
is beneficial to the dental practice that
the fact that your dental practice uses it.
marketing material includes information
Doing so becomes a win-win situation
on the use of the OPMI. This could be
for patients and dentists: patients get
done by means of various media such
better treatment and practices become
as paper print (i.e. office brochures and
more profitable.
Health benefits to the dentist
newsletters), a practice website and
the social media. Informing patients of
the fact the practice uses OPMIs also
underlines to them that the practice
stands out above and beyond other
practices and is very advanced.
For dentists who have taken OPMI
training courses, it is recommended
that they display any certificates they
obtained for patients to see and
Figure 7.9 A dentist being trained in
appreciate their dentist’s proficiency in
the use of an OPMI demonstrates good
the use of the OPMI.
Improved ergonomics and posture with
Better health results in the following:
the OPMI become more obvious as the
•Ability to provide more treatments
dentist becomes more proficient in its
use. Improved ergonomics also means
health benefits for the dentist. This may
be in the form of reduced back and neck
throughout the day/week. This also
means increased patient throughput.
•Reduced downtimes due to injuries
that plague many dentists leading to a
better quality of life.
•Potentially longer dental career.
Better health makes for better work and
better business!!
7 Practice Management
Financials of the OPMI
Return on Investment – Example
Patient fee $1,000
1 per week
average price
of an OPMI
Patient fee $500
1 per week
Patient fee $1,000
1 per month
Patient fee $500
1 per month
The increase in acceptance rates,
1 23 4 5678 910
improved quality of treatment, greater
efficiency and enhanced reputation that
may come with the use of the OPMI can
result in financial benefits.
Patient fee
For instance, performing one root canal
Frequency of
Income from
in 1 year
Income from
procedure over
10 years (more
after inflation)
1 per month
$60,000 ++
1 per week
$240,000 ++
per month that the dentist is not able
to perform without the magnification of
an OPMI, may make it possible to pay
Molar root canal $500
for the OPMI or the loan of an OPMI
in only a few years. This is only one
example of how easy it is to justify the
financial investment needed to purchase
(48 weeks)
an OPMI.
1 per month
$120,000 ++
1 per week
$480,000 ++
(48 weeks)
Table 7.1: The table demonstrates the return on investment of one common procedure (example fees),
which the dentist may now be able to perform thanks to the OPMI:
Patient perception of the dentist, their
office and their dental work can be
Percent increase
enhanced with the OPMI. With proper
to dental fees
Increased income
Increased income over 10 years
in 1 year
(more after inflation)
patient understanding of the benefits
1 percent ($400,000)
of the OPMI, it is easier to justify an
increase to your dental fees.
2 percent ($400,000)
5 percent ($400,000)
Table 7.2: The table demonstrating the financial returns of increasing procedure fees in practices
that, for example, gross $400,000 and $800,000 annually.
Quite simply, when used regularly, the OPMI pays for itself very easily and quickly.
The Authors
Dr. José Aranguren Cangas
Dr. Kristina Badalyan
Dr. Rino Burkhardt
Dr. Annett Burzlaff
Dr. Maciej Goczewski
Dr. Manor Haas
Oscar Freiherr von Stetten
Dr. Bijan Vahedi
Dr. Maxim Stosek
Dr. Claudia Cia Worschech
Associate Professor of
Graduated from the Yerevan
Graduated from University
Graduated from the Free
Graduated from the Medical
Graduated from the
State examination at the
Graduated from University
Graduated from the UPJS
Graduated from UNICAMP,
Endodontics at the Rey Juan
State Medical University,
of Zurich and received his
University of Berlin in
University of Gdansk in
University of Toronto,
FU Berlin. Own practice
of Leipzig and received
University in Kosice, Slovakia
where also received her
Carlos University in Madrid.
Armenia specializing in
doctorate from the
cell biology in 1995. As
1999. Experience working
Faculty of Dentistry in
since 2001, featuring OPMI
doctorate from the Medical
in 2000.
masters, doctorate and
Dentistry in 1996. Attended
Medical Faculty of the
postdoctoral research
at GKT, King‘s College,
1997. Immediately invited
support and specialization
Faculty of University of Ulm.
Since 2003, has run
postgraduate degrees.
Coordinator Professor
a postgraduate programme
same university.
fellow, specialized in light
London, UK and Académie
to teach at the University
in endodontics, as well as
Specialist in endodontics of
own practice limited to
Currently President of
of Adult Comprehensive
in Endodontic Surgery at
EFP (European Federation
and electron microscopy in
Internationale pour
of Toronto Restorative and
minimally invasive dentistry.
DGET (German Association
microscopic restorative
Brazilian Academy of
Dentistry UEM (2008-2010).
Central Institute of Scientific
of Periodontology) certified
cell biology at the German
Implantologie Orale, Paris,
Prosthodontic Departments.
Own endodontics referral
of Endodontology an Dental
dentistry in Presov,
Microscope Dentistry /
Research in Dentistry,
specialist in periodontology.
Cancer Research Center
France. He has earned his
Alongside his teaching
practice since 2006.
Traumatology), certified
Slovakia, spreading idea
ABRAMO from 2014 to
Professor of the
Moscow, Russia, where she
Received his master’s degree
and managed the Central
Ph.D. title in 2010.
positions, practiced general
member of ESE (European
of microinvasive treatment
Postgraduate Programme in
gained her Ph. D. Continues
from the Medical Faculty
Laboratory for Microscopy
For most of his career, he
dentistry and pursued
Numerous lectures
Society of Endodontology)
succesfully not only in
Endodontics and Restorative
to work at the Institute
of the University of Berne
at the University of
has worked at his private
endodontic research.
and publications on
and international member
patients but also and mainly
Active member of Editorial
Dentistry at the Rey Juan
and runs private practice
(MAS in Periodontology).
documentation with an
of the AAE (American
among dental community in
Board at ESTETICA, an
Carlos University.
in Moscow, where she
important journal about
Title degree in dentistry
clinic and presided at the
Polish Society of Microscopic
Pursued his endodontic
OPMI, as well as working
Association of Endodontics)
and microsurgical specialty
ergonomically correct in a
Runs a private practice in
team with the OPMI
Augsburg / Germany limited
Lectures and publishes
to endodontics.
nationally and internationally
specializes in implantology
Has maintained a private
In 2002, started as
and oral surgery.
practice in Zurich limited
professional trainer for
Main fields of interest are
training in the Graduate
to periodontology and
microscopy and imaging
ergonomics and microscopic
Endodontics Programme at
implantology since 1995.
systems at Olympus Life and
dentistry; six-handed and
the Albert Einstein Medical
Key Opinion Leader for
Currently vice-president of
on composite layering
Owner and scientific
four-handed variants in
Centre in Philadelphia,
multiple dental companies
techniques, endodontics
director of GENIO: center of
both. Shares his experience
regarding the development
Speaker at congresses,
and nowadays mainly OPMI
excellence for microdentistry
of new products. Worked
lectures, courses and master
based dentistry and dental
in Brazil.
from the Universidad
aesthetic dentistry in Brazil,
published by Dental Press.
Europea de Madrid (UEM
Has held numerous
courses, master classes
Material Science and Sirona
and congresses in ten
Dental Services. Manager
Specialist in endodontics,
largest cities of Russia and
for training, application
organizing numerous courses
Specialty Certified in
and support in dental and
and attending conferences
Has run a private specialty
for ZEISS as KOL for
classes nationally and
Has held numerous
Endodontics, University of
Active Member of NAED
ophthalmic microscopy at
as a speaker.
practice in Toronto, limited
documentation with an
Parttime teacher at the UPJS
courses, master classes
Southern Mississippi (USM)
(National Academy of
Carl Zeiss Meditec AG since
to dental implantology,
University in Kosice, Slovakia.
and congresses all over the
Aesthetic Dentistry) and
microsurgery and
world, including lectures
In private practice limited to
Opinion Leader of Dentsply
endodontics. Gained decade
in Japan, USA, Lithuania,
endodontics in Madrid
and Camlog. Also scientific
of experience incorporating
Portugal, Argentina and
editor of Quintessence
the OPMI exclusively into his
Has run private practice
in Sao Paulo, Brazil, since
The Editors
Dr. Tony Druttman
Dr. Greg Finn
Slaven Sestic
1981 Qualified B.Ch.D. Leeds
Qualified as a dentist in Brisbane in
Carl Zeiss Meditec AG
University, 1987 M.Sc. Conservative
1982, specialist prosthodontist with a
Field Education Manager
Dentistry, Eastman Dental Hospital,
referral practice in London, as well as
London University. Since 1999 a
a clinical lecturer at the UCL Eastman
registered specialist and practice
Dental Institute. He runs courses on
limited to endodontics. His principal
microscopes in dentistry at EDI with
area of interest is non surgical re-
Dr. Tony Druttman
He has been a member of the
British Endodontic Society for over
Our Authors TEAM in Barcelona, Spain in 2013
30 years and was President of the
Society in 1994. He is also a Certified
Member of the European Society of
Inspiration is one thing and you can’t
He is a visiting specialist teacher
control it, but hard work is what keeps
at the Eastman Dental Institiute,
where he teaches endodontics and
the ship moving. There are no secrets to
runs courses with Dr Greg Finn on
success. It is the result of preparation,
microscopes in dentistry.
hard work, and learning from failure.
He has lectured both in the UK
We would like to thank you sincerely
and at international meetings on
endodontics and radiography in
for all your enthusiasm and hard work,
thank you for all good times, days filled
He is on the editorial board of
with pleasure and great memories.
Endodontic Practice Journal and
is a contributing author.
Your ZEISS Team
Pictures credits
Page 11,13
Dr. Claudia Cia Worschech
Page 152
5.20 Dr. Maxim Stosek
Page 14-17 Carl Zeiss Meditec AG
5.21, 5.22 Dr. Claudia Cia Worschech
Page 18-19
Dr. Rino Burkhardt
Page 153 5.23, 5.24 Dr. Claudia Cia Worschech
Page 20-21 Carl Zeiss Meditec AG
5.25, 5.26 Dr. Maxim Stosek
Page 24
Carl Zeiss Meditec AG
Page 154-165
Dr. Claudia Cia Worschech
Page 25
Carl Zeiss Meditec AG, Fotolia
Page 166-167
Dr. Maxim Stosek
Page 26-27 Dr. Claudia Cia Worschech
Page 168-172
Dr. Claudia Cia Worschech
Page 28 Fotolia
Page 173
Carl Zeiss Meditec AG
Page 30-36
Carl Zeiss Meditec AG
Page 174-175
Dr. Claudia Cia Worschech
Page 37
1.8 Oscar von Stetten
Page 180
Dr. Bijan Vahedi
Page 38-51
Carl Zeiss Meditec AG
Page 182-183
Oscar von Stetten
Page 54-67
Carl Zeiss Meditec AG
Page 184
Dr. Kristina Badalyan
Page 68 Dr. Maciej Goczewski
Page 185
Oscar von Stetten
Page 69 Oscar von Stetten
Page 186
Carl Zeiss Meditec AG
Page 72-73
Dr. Kristina Badalyan
Page 190
Carl Zeiss Meditec AG
Page 74-75 Dr. José Aranguren Cangas
Page 192
Dr. Manor Haas
Page 76-78
Dr. Tony Druttman
Page 193
7.5 Carl Zeiss Meditec AG,
Page 79 3.8a, 3.8b, 3.8c Dr. José Aranguren Cangas
7.6, 7.7 Dr. Manor Haas
3.10, 3.11 Oscar von Stetten
Page 195
Carl Zeiss Meditec AG
Page 80-81 Dr. Tony Druttman
Page 197
Carl Zeiss Meditec AG
Page 82
3.17 Dr. Tony Druttman,
3.18a, 318b Dr. José Aranguren Cangas
Page 83-85
Dr. Tony Druttman
Page 86
3.22a, 3.22b, 3.22c Dr. Tony Druttman
3.23 Oscar von Stetten
Page 87-90
Dr. Tony Druttman
Page 91
Oscar von Stetten
Page 92 3.27, 3.28 Dr. José Aranguren Cangas
3.29a, 3.29b Dr. Tony Druttman
Page 93-94
Dr. Tony Druttman
Page 95
3.39 Dr. Tony Druttman
3.40 Carl Zeiss Meditec AG
Goeschwitzer Straße 51-52
Page 96-101 Dr. Kristina Badalyan
07745 Jena, Germany
Page 104-121 Dr. Rino Burkhardt
Page 125-127
Dr. Rino Burkhardt
Telefon: +49 3641 220-0
Page 134-137
Dr. Claudia Cia Worschech
[email protected]
Page 138-139
5.2; Dr. Claudia Cia Worschech
5.3; 5.4; 5.5; 5.6 Dr. Maxim Stosek
Page 140-145
Dr. Claudia Cia Worschech
Page 146
Dr. Maxim Stosek
All rights reserved. No part of this book may be
Page 147
5.13 Dr. Claudia Cia Worschech
reproduced or transmitted in any form by any
5.14, 5.15a, 5.15b Dr. Maxim Stosek
means, electronic , mechanical, photocopying,
Page 148
Dr. Claudia Cia Worschech
recording, or otherwise, without the prior
Page 149
Carl Zeiss Meditec AG
written permission of the publisher.
Page 150-151
Dr. Maxim Stosek
For Information, contact Carl Zeiss Meditec AG
Carl Zeiss Meditec AG
Copyright©2014 Carl Zeiss Meditec AG
Download the Microscopic
Dentistry Practical Guide under:
EN_30_200_0149 I Printed in Germany AW-CZ-VII/2013 Koo International Edition: Not for use in the United States.
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