This document discusses various diagnostic aids and applications of cone beam computed tomography (CBCT) scanning in orthodontics, such as localization of impacted teeth and assessment of bone thickness. It provides examples of CBCT scans of impacted teeth in a 13-year-old patient. It also describes 3D imaging software used to visualize craniofacial anatomy from CBCT and other scans. Clear aligners for orthodontic treatment are discussed, including the Invisalign system and steps of fabrication from impressions to aligner delivery.

1. GOOD MORNING

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3. ADVANCED
DIAGNOSTIC AIDS
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4. ○ Localization of
impacted teeth
○ Assess level and extent
of resorption of teeth
adjacent to impacted
teeth.
○ Bone scanning before
implant placements
and surgeries.
○ Assessment of bone
thickness for tooth
movements
Orthodontic uses
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5. CT SCAN CASE : MISS SHILPA 23/F
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7. ○ Software allows for reformatting and viewing the
image data from any point of view in straight or
curved planes and in 3 dimensions.
○ With these software tools, the anatomy can be peeled
away layer by layer to locate the desired section.
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8. 13-YEAR-OLD MALE PATIENT
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Two horizontally impacted permanent maxillary
right teeth, a impacted central incisor, and
impacted canine

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Transverse CT scans
s h o w h o r i z o n t a l
i m p a c t i o n o f t h e
m a x i l l a r y r i g h t
p e r m a n e n t c e n t r a l
incisor (I) and canine (C)
in close proximity to the
nasopalatine canal (N).

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3D CT : In addition, they
revealed a markedly
s u p e r o l a t e r a l l y
orientated dilaceration in
the apical third of the
root of the central incisor,
which had not been seen
on the panoramic and
periapical radiographs
b e c a u s e o f
superimposition of the
two teeth

11. ○ Dolphin 3D allows visualization and analysis of
craniofacial anatomy from data produced by cone beam
computed tomography (CBCT), MRI, medical CT and 3D
facial camera systems.
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DOLPHIN 3D SOFTWARE

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View impacted teeth from any angle
Isolate desired region of interest
Airway measurements
Slice display of airway
volume and most
constricted area
Display of airway
volume and most
constricted area

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DEMO OF 3D SOFTWARE : CLICK

14. RADIOVISIOGRAPHY
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Parts : X-ray source, Intraoral
sensor, Computer
It is used to digitize,
process and store
information received
from the sensor
within 5 – 10 sec
and display image
on computer screen.

15. APPLICATIONS OF CAD CAM
○ Making of dental
restorations
○ Brackets : torque in base
○ Self ligating brackets
○ Lingual brackets
○ Implants
○ Invisilign 15

16. ○ Acronym for What You See Is What You Get
○ Prototyping could become a new tool for
fabricating brackets and other precision
accessories for specific needs.
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Structure
d
triangular
language

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Pre treatment – elevation in
palatal mucosa

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20. Image from STL file after elimination of all the
tissues and structures
Triangular mesh
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22. CLEAR ALIGNERS
AND INVISALIGN

23.
“A smile is a curve that sets everything straight.” Phyllis Diller

24. Smiles like this can be attained with
braces but sometimes traditional braces
can be avoided by using Invisalign or
other types of clear style aligners

26. UPPER
INVISALIGN
APPLIANCE

27. UPPER AND LOWER INVISALIGN APPLIANCE
• UPPER IS FULLY SEATED AND BEARLY NOTICABLE
• LOWER IS INTENTIONALLY PULLED UP A LITTLE FOR BETTER
VISUALIZATION

28. INDICATIONS
● Intrusion and extrusion
● Midline correction
● Minor crowding(less than 4 mm especially from canine to
canine)
● Space closure(3-6mm)
● Rotation control,especially rotated incisors
● Crossbite correction
● Arch expansion and contraction
● Passive/active retainer
● Minor relapse correction

29. ADVANTAGES
● Esthetic
● Removable
● Easy manufacture
● Useful in borderline cases
● Speedy
● Results are fine
● Less speech problems
● Cost effective
● More biologic for tissue response
● Acts as a relapse breaker and retainer
● As the margins are 4-5 mm above the marginal gingiva it is comfortable to the patient
● Causes less irritation
●

30. DISADVANTAGES
● Not everyone is a candidate for Invisalign
● Treament is for adults and cannot be used if deciduous teeth remain
● It is designed for certain tooth movements
● Cost is more than metal braces
● As they are removable they require constant motivation to be worn
consistantly
● Can be misplaced
● Cannot be used in extraction cases
● Treatment plan cannot be changed once the appliance series has begun

31. PRIOR TO STARTING TREATMENT
• Check for caries and periodontal problems
• Axial inclination of the teeth
• 3rd molar position
• Patient cooperation
• As certain tooth movements are more predictable
than others ,case selection is ultimately determined
by the manufacturer .

32. CLINICIAN’
S OFFICE
ALIGN
TECHNOLO
GY
CLINICIAN”
S OFFICE
ALIGN
TECHNOLO
GY
SHIPPED
CLINCHECK
SENT VIA
INTERNET
STEPS IN FABRICATION OF INVISALIGN

33. CLINICIAN’S OFFICE
CONSULTATION
RECORDS
IMPRESSION
TREATMENT
PLANNING FORM

34. ALIGN® TECHNOLOGY : INVISALIGN APPLIANCE
○ It is an ‘invisible’ way to straighten teeth using thin, clear, overlay
sequential appliances.
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Impressions
are made using
Polyvinyl
Siloxane
Impression and
bite send along
with a detailed
treatment plan.
advanced imaging
technology transforms
plaster models into a
highly accurate 3-D
digital image.
A computerized movie -
called ClinCheck® -
depicting the
movement of teeth
from the beginning to
the final position is
created.
After wearing all
of the aligners in
the series,
customized set of
aligners are made from
these models, sent to
the doctor, and given to
the patient. Pt to wear
each aligner for about
two weeks.
From the approved file,
laser scanning to build a
set Invisalign® uses of
actual models that
reflect each stage of the
treatment plan.
Using the Internet, the
doctor reviews the
ClinCheck file - if
necessary, adjustments
to the depicted plan
are made.
Procedure

36. ALIGN TECHNOLOGY
IMPRESSION
SCANNED
BITE
REGISTRATION
TREAT SOFTWARE
PROCESS
CLINCHECK

37. ALIGN TECHNOLOGY
IMPRESSION
SCANNED
BITE
REGISTRATION
TREAT SOFTWARE
PROCESS
CLINCHECK
VIRTUAL
INVISALIGN
PRACTICE
MODIFY/ACCEPT
ALIGNER
FABRICATION

38. RECORDS
● The clinician should have the following records
● Photographs
● Full mouth IOPA
● OPG

39. IMPRESSION MATERIALS
Impression Materials are used to record the dimensions and
spatial relationships of oral tissue .
• Alginate
● Polyether
● Polyvinylsiloxane
● The impression should be accurate and stable as it is the basis
for the 3D dental arch image that is scanned into the computer.

40. SCANNING PROCESS
The term scanning is used to describe the process of
converting a physical object into three dimensional
electronic data.
Scanning methods:
1.Laser scanning
2.Destructive scanning
3.White light scanning
4.Computerized tomography

41.
LASER SCANNING
● A laser beam is projected on the object being scanned
and the reflection of the beam is recorded.
● The object being scanned is rotated to several
predetermined positions so that multiple views can
be recorded.
● The recordings made from these different views are
incorporated together to produce a 3 D electronic
image of the object.

42. BITE REGISTRATION
● The clinician takes the bite in centric occlusion i.e
maximum intercuspation.
● An accurate impression of the occlusion will help in
achieving good results.

43.
MATERIALS
DURAN( Scheu Dental, Germany)
•Soft thickness(0.5mm)
•Medium thickness(0.62 mm)
•Hard thickness(0.75 mm)
• It is thermoplastic
•Given for a period of 3 weeks, a week each.
•Medium aligner reduces discomfort before
placing hard clear aligners.

44.
TOOTH MOVEMENT
● There is a greater surface area of force application to the
tooth.
● Bodily movement is possible, particularly if the entire
crown is held tightly with no space between the
appliance and tooth.
● For the appliance to fit tightly, it may be necessary to
add attachments.
● Forces involved for 0.02 mm activation are light
continuous nature due to elastic properties of the
appliance and small magnitude of individual activation
at each stage.

45. ATTACHMENTS
• Tooth colored acrylic called attachments are bonded
to the front or back side of specific teeth to give
aligners more grip on teeth to move them in desired
position.
• They are a part of treatment and removed by
orthodontist when the treatment is completed.

46. SPACE GAINING IN
CLEAR ALIGNERS
● Space can be gained by
1.Extraction
2.Expansion
3.Interproximal reduction
➢In clear aligner treatment , interproximal reduction is
done with high speed drill and sandpaper like strips /
disks and does not require anesthesia.
➢Always use a cutting device that is thinner than the
enamel to be removed.

47. TREATMENT TIME
● 1st clear aligner-0.5 mm tooth movement-4 weeks
● 2nd clear aligner-1mm tooth movement-4 weeks
● 3rd clear aligner-0.5 mm tooth movement-4 weeks
● Hence the treatment time will be around 12
weeks

48. Problems During Treatment
Any discrepancy between the actual clinical
appearance of occlusion and the virtual treatment
sequence program indicates that treatment should be
fully reviewed
Reasons for discrepancy
• Patient loses appliance.
• Patient is not wearing for sufficient time(atleast 20
hours per day).
• Appliance has not been fully seated.

49. INVISALIGN CLEAR ALIGNERS
Model has to be sent to ALIGN
TECHNOLOGY which is in USA and
Singapore.
➢Treatment is stepwise
➢No 3rd party involved
➢In office lab procedure
They provide 30 sets of aligners which
is to be used sequentially
3 sets of 3 aligners are custom made
and given to the patient sequentially.
Margins of aligners ends at the
marginal gingiva
Margins are 4-5mm above the
marginal gingiva.
If one tray is not worn regularly,
patient has to switch to the older tray
and it may not fit properly.
If tray is not worn, clinician can return
to the cast used in previous step.
So, new set of 30 alignrers has to made Clear aligner can be used in mixed

50. COW CATCH ALIGNERS
● Used to correct open bite.
● Teeth to be extruded are
supplied with buttons and
connected to opposite arch
with elastics where buttons
are attached to aligners
● When the expected
extrusion is achieved the
respective teeth will contact
the inner surface of the
aligner so that no
additional extrusion occurs

51. MODIFIED COW CATCH ALIGNER
● If the patient cannot tolerate the limited opening
while wearing cow catch aligners with intermaxillary
elastics or needs to verbally communicate a lot, it is
recommended to use an appliance modification
characterized by buttons on the lingual sides.
● More convenient and comfortable

52. The Essex system
Creating space within
the appliances
Inducing tooth moving
forces in the appliance
How the system works

53. Early Correction of Developing Anterior
Crossbite with Modified Essix Appliance
Amarnath Biradar, G Shiva Prakash, Mala Ram Manohar