Description of Dental Loupes and the Dental Operating Microscope.

1. Magnification in
Dentistry

2. ONLY THING IN LIFE WHICH IS CONSTANT IS CHANGE

3. Technology constantly forces us to relook
at are processes and improve

5. • It may seem surprising that the microscope is not a high-tech
instrument.
• It has been used in the medical field for over 50 years.
• Zeiss Company states that it first introduced
to Otolaryngology in 1950s
to Neurosurgery in 1960s
to Endodontics in 1990s
• Dentistry, therefore, is about 40 years behind medicine in this
respect.

6. • In dentistry, Endodontists were first to introduce it
• Gary Carr is regarded as the father of microscopic endodontics

7. Why is Magnification important??

10. Resolution • The ability to differentiate between two
closely positioned bright objects.

11. • The resolving power of the unaided human eye is
only .2 mm.
• In other words, most people who view two
points closer than .2 mm will see only one point.
• The film thickness of most crown and bridge
cements is 25 microns (.025 mm), or well beyond
the resolving power of the naked eye.
• Operating microscope can raise the resolving
limit from 0.2mm to 0.006 mm (6 microns), a
dramatic improvement.
WHAT IS THE
LIMITS OF
HUMAN
VISION….??

12. How do we improve
our ability to resolve
small objects
• Use of magnification!!!
• Use of light!!!

13. Lets start with
few basic
concepts of
optical
properties
Magnification
• Magnification of an image is a relative
value and has to do with the size of an
image as projected onto the retina of the
eye
• The magnification of an image is
increased by simply decreasing the
distance between the eye and the object
in question.

15. Working
distance • The distance at which the optics of a
Loupes or Microscope are sharply
focussed.
• Distance should be sufficient to place the
hands and the instruments comfortably
between the Loupe or microscope and
the operating area.

16. Depth-of-Field /
Depth-of-Focus
• The range over which the image
remains sharply focussed.
• These terms relate to the area in
front of, and behind, the point of
perfect optical focus, where
sharp focus is maintained.

17. Field of
view
• The area that can be seen under magnification
at normal working distance

18. Tools for magnification in dentistry
Magnifying loupes
Operating microscopes

19. LOUPES
Loupes are classified by the optical method by which they produce
magnification.
There are 3 types of binocular magnifying loupes:
• Diopter, flat-plane, single lens loupe,
• Surgical telescope with a Galilean system configuration (2-lens system)
• Surgical telescope with a Keplerian system configuration (prism roof
design that folds the path of light).

20. • The diopter system relies on a simple
magnifying lens.
• The degree of magnification is usually
measured in diopters.
• One diopter (D) means that a ray of light that
would be focused at infinity now would be
focused at 1 meter (100 cm or 40 inches).
• A lens with 2 D designation would focus to 50
cm (19 inches); a 5 D lens would focus to 20 cm
(8 inches).
• Diopter(D) is not equal to magnification(X).
Diopter

21. • The only advantage of the diopter
system is that it is the most
inexpensive system.
• But the plastic lenses that it uses
are not always optically correct.
• Furthermore, the increased image
size depends on being closer to the
viewed object, which can
compromise posture and create
stresses and abnormalities in the
musculoskeletal system

22. Galilean system
The Galilean system provides a
magnification range from 2x to 4.5x
and is a small, light, and compact
system

23. Keplarian system
These are prism loupes use
refractive prisms and are actually
telescopes with complicated light
paths, which provide higher
magnifications.

24. Both systems produce
• Superior magnification.
• Correct spherical and chromatic
aberrations.
• Excellent depth of field.
• Capable of increased focal length (30–
45 cm), thereby reducing eyestrain
and head and neck fatigue.

25. TYPES OF
LOUPES
TTL-Through the lens
Flip up Loupes
Head Mounted loupes

26. Loupes with lighting

27. Importance of
choosing the
right light
Light intensity
LED LIGHT WITH INTENSITY
FROM 40,000 LUX ONWARDS

28. Importance of
choosing the
right light
Color rendering
Pure white LED’s provide ‘true
color’.
Unfortunately, many LED headlights on
the market display a blue beam, rather
than a pure white beam. This blue
beam will result in severe color
distortion and is most commonly found
in very inexpensive LED lights.

29. Importance of
choosing the
right light
Homogenity

30. • Limited magnification
• Illumination is not as high as a
microscope.
• Loupes with higher magnification are
uncomfortable on the nose or head due
to their large size and increased weight.
• Imaging and documentation not possible.
Disadvantages

32. Microscopes
• The operative microscopes
provides greater
magnification and
illumination & functions as
an extension of loupes

33. Parts of a operative
microscope
• The operating
microscope consists of
three primary
components —
• The supporting
structure,
• The body of the
microscope, and
• The light source.

34. The Supporting
Structure
• It is essential that the
microscope be stable while in
operation, yet remain
manoeuvrable with ease and
exceptional precision,
particularly when used at
high power.
• The supporting structure can
be mounted on the floor,
ceiling, or wall.
• As the distance between the
fixation point and the body of
the microscope is decreased,
the stability of the setup is
increased.

35. The
Supporting
Structure
WALL MOUNTED/HIGH WALL MOUNTED

36. The
Supporting
Structure
FLOOR MOUNTED

37. The
Supporting
Structure
CEILING MOUNTED

38. The
Supporting
Structure
TABLE MOUNTED

39. The
Supporting
Structure
HEAD MOUNTED MICROSCOPE

40. • Eye piece
• Binoculars
• Magnification changers
• Objective lens
• Light housing
• Accessories
Body of the Microscope

41. Eyepieces
Generally available in
magnification 6.3x,
10x, 12.5x, 16x, and
20x.
The end of each
eyepiece has a rubber
cup that can be
lowered for clinicians
who wear glasses.
Have adjustable
diopter settings (adjust
for accommodation i.e.
the ability to focus the
lens of the eyes) .
Diopter setting also
adjusts for refractive
errors.
Ranges from -5 to +5

42. Binoculars
• Function to hold the eyepieces
• IPD set by adjusting the distance between
two binocular tubes.
• Once diopter setting and IPD are set, they
are not to be changed until the
microscope is used by a surgeon of
different optical requirements
• Comes in different focal lengths
• Available with straight, inclined or
inclinable tubes

43. Magnification Changers
• Available as either three/five/six step manual changers or power
zoom changer
• Series of lenses that move back and forth on a focusing ring to give
a wide range of magnification
• Controlled by either a foot control or a manual override.
• Foot control allows the clinician to
adjust magnification and focus
without taking the hands or eye
away from the surgical field.

44. Objective Lens
• Nearest to the surgical field.
• Focal length of it determines distance between the lens and the
surgical field
• Available with focal length ranging from 100 to 400mm
• A 200-250mm objective lens is recommended.
– Reason :
– There is enough room to place surgical instruments and still be
close to the patient.

46. Magnification determined by :
• Power of the eyepiece
• The focal length of the binoculars
• The magnification changer factor
• The focal length of the
objective lens

47. LIGHT HOUSE (Illumination)
• Microscope illumination can be of two varieties.
• Originally, microscopes had only externally mounted
independent illuminators transmitting light but creating some
shadows and unable to get down deep into cavities.

48. Co axial illumination
• This means that the light from the illuminator bulb is re-routed to a point very
near the viewing axis of the microscope and is projected down through the same
objective lens used for viewing
• No shadow.
• Under the microscope, a specific amount of light will be projected and any change
made in microscope magnification will have no effect on the amount of light being
projected from the microscope.

49. • However, Changes made in the magnification of the
microscope do, increase or decrease the amount of light
which will be projected back through the microscope and
onto the retina of the eye of the viewer.

50. • Therefore an increase in magnification is accompanied by a
decrease in illumination
• Several manufacturers, however, have gone to great efforts to
minimize this by using ultra-wide, multi-coated optics.
• Therefore, this effect will be difficult to notice, if not
impossible.

51. Recommended lighting
• The light source can be powered by a Halogen light bulb or by
a Xenon light.
• Some halogen lights provide an artificial yellow light, which is
not ideal for documentation, so any product must be carefully
selected.
• LED’S are the light sources of choice now.

52. ACCESSORIES
• Beam Splitter
• Filters
• Eyepiece With Reticle Field
• Monitors/ LCD screens
• Assistant Scope
• Cine Or Photographic Adapters

53. Beam Splitter :
• Function is to supply light to accessories such as a camera or
an auxiliary observation tube.
• 50:50 beam splitter along with other configuration available

54. • Photo adapters attach camera & video camera to beam splitter
• Photo or cine adapters also provide the necessary focal length so that the camera
records an image with the same magnification and field of view as seen by the
operator

55. Filters
• Reason for filters….??
• Green for surgical procedures - it removes the confounding
red reflections of the blood
• Orange filter – prevents premature setting of composite resin.

56. Eyepiece with reticle field
• An eyepiece reticle is a glass disc with a pattern on it that fits
at the optical plane inside a microscope eyepiece.
• An eyepiece with a reticle field can be substituted for a
conventional eyepiece and can prove an invaluable aid for
alignment during videotaping and 35 mm photography.

57. LCD screen

58. Assistant scope/ Co-observation tube
• Useful to assistant.
• Also better to assistant than looking at monitor.
• Can be monocular or binocular.

59. COOBSERVATION TUBE
PHOTOGRAPHIC
ADAPTER
CINE ADAPTER
PISTOL GRIPS
EYEPIECE WITH A
RETICULE FIELD

60. Pre requisites For The Use of The Microscope In Non-
Surgical Endodontics
• Rubber Dam Placement
• Indirect View and Patient head Position
• Mouth Mirror Placement
• Some Key Instruments

61. Rubber dam placement
• While using operating microscope rubber dam becomes a
necessity.
• Most of the procedure is performed using a mirror and indirect
vision
• If rubber dam is not used then the mirror would fog immediately
from the exhalation of the patient.
• Thus, the powerful microscope
magnification and illumination
would be rendered totally useless

62. Indirect view and patient head position
• It is nearly impossible to view the pulp chamber directly
under the microscope
• Instead, the view seen through the microscope lens is a view
reflected by way of a mirror.

63. Some key instruments
• The ability to locate hidden canals is the most important
and significant benefit gained from using the microscope.
• To do this effectively and efficiently, clinicians must use
specially designed microinstruments.
• There is only a tiny space between the mirror and the
tooth for a finger with a file to move around files specially
designed by Maileffer, called microopeners, have a handle
with different sized tips and can be extremely useful.

65. ULTRASONIC TIPS
CPR TIPS
BUC TIPS
STARTEX TIPS

66. MICROMIRRORS

67. In chronological order, the preparation of the
microscope involves the following maneuvers:
1 Operator positioning
2 Rough positioning of the patient
3 Positioning of the microscope and focusing
4 Adjustment of the interpupillary distance
5 Fine positioning of the patient
6 Parfocal adjustment
7 Fine focus adjustment
8 Assistant scope adjustment

68. Most appropriate operating position is a combination of
I. Patient Head Position
II. Dental Chair Position
III. Microscope Position
IV. Surgeon Position
V. Assistant Position
VI. Assistant observation Devices

69. Patient Head Position
• Ensuring Patient comfort during surgery
utmost important
• No straining/torquing of head & neck
muscles
• Occlusal plane be Parallel to floor for
mandibular surgery, perpendicular for
maxillary surgery
• Head be comfortably centered or slightly
turned

70. Microscope Position
• Most endodontists prefer Ceiling mounted operating
microscope
• Suspension arms supports and position the microscope in
horizontal & vertical dimensions
• An addition of a Rotational attachment (Mora) or a extender
makes the positioning of the Microscope easier.

71. Selection of Binocular critical
• Inclinable binocular are the best one.
• Inclinable tube provide the operator with
additional postural comfort during long
procedures but they are comparitively
expensive.

72. • Should Use an Adjustable stool
• Thighs parallel to floor
• Arms relaxed, and placed
comfortably at side
Surgeon Position

73. A well designed microsurgery may need
three assistants
• FIRST ASSISTANT :
responsible for suctioning, usually
seated
• SECOND ASSISTANT :
Passes instruments, positioned next to
the surgeon’s dominant site
if a front delivery system is used,
positioned across the surgeon
• THIRD ASSISTANT :
Incharge of the video and photographic
functions
Assistant position

74. The Laws of Ergonomics
• An understanding of efficient work flow using a microscope
entails a knowledge of the basics of ergonomic motion.
• Ergonomic motion is divided up into five(5) classes of motion:

77. • That all instruments and equipment needed for a procedure
are within reach of either the clinician or the assistant,
requiring no more than a class IV motion,
• And that most endodontic procedures are performed with
class I or class II motions only
• Therefore, the circle of influence design principle places the
OM at the center and all other things required within the
circles
Circle of influence

78. Circle of influence

79. Some interesting
cases

80. Retrieval
of broken
files
1
With the more
frequent use of
nickel-titanium
rotary files in
general
dentistry, the
incidence of
file separation
within the
canals has
increased.
2
When the file is
broken at the
apex, the
microscope
cannot be of
help.
3
If the file
breaks within
the coronal
half of the
canal,
however, then
the microscope
is essential to
guide the
clinician to
retrieve the
broken files.
4
The broken file
can be
removed while
minimizing the
damage to the
surrounding
dentin.

82. CBCT assessment of
thermoplasticized
obturation of a C-
shaped canal

83. Case report • Female patient, aged 40 years, reported to the
department of Conservative Dentistry and
Endodontics with pain in the lower left back
tooth region.
• On examination,deep class V caries was
observed with respect to 37.IOPA reveals
radiolucency involving pulp.Pulp vitality testing
revealed no response to cold test,heat test and a
delayed response to EPT.CBCT revealed a C-
shaped canal configuration which had a
distobuccal apical exit.
• Access opening was done wrt 37,working length
was determined as 15 mm.Apical
instrumentation was done using K-files upto size
60 K file.Circumferential filing was done.3 rounds
of Ca(OH)2 dressing was placed.Obturation was
done using Continous wave obturation technique
and System B-Elements system .Amalgam core
build up was done

85. CORONAL THIRD-7.5 MM FROM APEX

86. MIDDLE THIRD-5MM FROM APEX

87. APICAL THIRD-2 MM FROM APEX

88. MB2
DETECTION

90. PLAIN
EYESIGHT
2.5X MAGNIFICATION 12.8X MAGNIFICATION

91. The distance between MB1 and
MB2, anything less that one-fifth
(i.e. 0.2mm) of a millimetre, it
becomes extremely difficult for the
human eye to resolve them as two
separate canals and that’s where
the role of magnification comes in
to play.
1
Furthermore, the intensity of light
from the microscope is much higher
than what is possible from the
loupe, and the nature of the
delivery is coaxial in the former.
This allows for better illumination of
the field and hence greater
visibility.
2

92. Management
of a Maxillary
Molar with 5
canals

94. Thank you