for Students of Orthodontics

1. Presented by-
Dr. Smaraki Mahapatra
PG 1ST Year (Orthodontics)
Under the guidance of –
Dr. Neetu Dabla
(Professor and Guide)
DIAGNOSTIC AIDS

2. CONTENTS
1.Introduction
2.Classification of diagnostic aids
3. Essential diagnostic aids
a. Case history
b. Clinical examination
c. Study models
d. Radiographs and facial photographs
4.Supplemental diagnostic aids
5. Recent advances
6. Conclusion
7. References

3. Introduction
 Comprehensive orthodontic diagnosis is
established by use of certain orthodontic clinical
implements called diagnostic aids in orthodontics.
 Diagnostic aids help in proper diagnosis and
treatment planning of orthodontist during
examining patients.

4. Classification of diagnostic aids
 Essential diagnostic aids
 Supplemental diagnostic aids

5. Essential diagnostic aids
 Case history
 Clinical examination
 Study models
 Certain radiographs
1.Periapical radiographs
2.Bite wing
3.Panoramic
 Facial photographs

6. Supplemental diagnostic aids
1.Specialized Radiographs
Cephalometric
Occlusal
Lateral jaw views
Cone shift technique
2.Electromyographic
examination of muscle activity
3.Hand-wrist radiograph to
asess bone age or maturation
age
4.Endocrine tests
5.Estimation of BMR
6.Diagnostic set up
7. Occlusogram

7. ESSENTIAL DIAGNOSTIC AIDS

8. CASE HISTORY
1
1.Personal details
2.Chief complaint
3. Medical history
4.Dental history
5.Prenatal history
6.Post-natal history
7. Family history

9. Personal details
 Name-
 Age-
 Sex-
 Case no-
 Occupation-
 Address-
 Date-

10. Chief Complaint
1. The patient’s chief complaints
should in his/her own words.
2.This helps the clinician in
identifying the priorities and
desires of the patient.
3. It can be elicited by way of an
interview or by asking the
patient to fill the questionnaire.

11. Medical history
A thorough medical history should be
taken . Conditions which might affect
orthodontic treatment include the
following.
Rheumatic Fever- Invasive
procedures such as band placement
and removal should be covered with
antibiotic regime.A chlorhexidine
rinse prior to the adjustment of a
fixed appliance is a useful adjunct.

12.  Epilepsy-Removable orthodontic appliances
are contraindicated in patients who exhibit
poorly controlled epilepsy due to risk of
airway obstruction during seizures.
 Diabetes Mellitus-Orthodontic treatment should
be avoided in patients with poorly controlled DM.
Periodontal evaluation is mandatory before
starting orthodontic procedure. Patients should be
have their normal meal and medications before
appointments.

13. Haemophilia
1. Care should be taken to avoid irritation in the gingiva, lip or
cheeks from the orthodontic appliances.
2. Care should be taken during insertion and removal of the arch
wire in order to avoid any injury to the oral soft tissues.
3.Elasteromeric ligatures are preferred over wire ligatures to secure
the arch wire as it reduces the risk of irritation of the soft tissues.

14. Dental history
 Components of past dental history includes
1. Previous restorative
2. Endodontic or Oral surgical treatments
3. Reasons for tooth loss of teeth
4. Experience with orthodontic appliance and
dental prosthesis
 By noting this , the dentist will get an accurate
idea of the importance he gives to good dental
treatment and how conscious he has been in
persuing a goal of good oral health.

15. Pre-natal history
 The pre-natal history should include information on
the condition of the mother during pregnancy and
the type of delivery.
 The use of certain drugs like thalidomide or affection
with some infections during pregnancy like German
measles can result in congenital deformities of the
child.
 Information should be gathered on the type of
delivery.
 Forcep delivery predispose to TMJ Iinjuries that can
manifest as marked mandibular growth retardation.

16. Post-natal History
 The post-natal history includes information on
the type of feeding, presence of habits and on
the milestones of normal development.
Tongue thrusting Thumb
sucking

17. Family history
 This is very important for many hereditary
diseases.
 Many diseases recur in families like
hemophilia, diabetes mellitus, hypertension
and heart diseases.

18. CLINICAL EXAMINATION

19. General examination
 Height and weight
 Gait
 Posture
 Body build

20. Extraoral Examination
1. Shape of head
2. Facial form
3. Facial asymmetry
4. Facial Profile
5. Facial divergence
6. Ant-post jaw relationship
7. Vertical skeletal relationship
8. Facial proportion
9. Examination of lips, nose, chin prominences

21. Intraoral examination
Examination of the following
1.Tongue
2. Palate
3.Gingiva
4.Frenal attachments
5.Tonsils and adenoids
6. Assessment of dentition

22. Functional examination
 Improper functioning of the stomatognathic system can result in
various malocclusions.
 The functional examination should include :
 Assessment of postural rest position and inter occlusal space
 Path of closure
 Assessment of respiration
 Examination of TMJ
 Examination of swallowing
 Examination of speech
22

23. STUDY MODEL
1.Orthodontic study models are accurate
Plaster reproductions of the teeth and
their surrounding soft tissues.
Uses-
1. They enable the study of the occlusion
from all aspects
2. They enable accurate measurements to
be made in a dental arch. They help in
measurement of arch length, arch
width and tooth size.
3. They help in treatment progress by the
dentist as well as the patient.
4. They help in assessing the nature and
severity of malocclusion.

24. RADIOGRAPHS
They are two types:- 1.Intraoral
2.Extraoral
 Intraoral is again divided in to 3 types:-
1.Periapical
2. Bitewing
3. Occlusal
 Extraoral radiographs:-
1.Panoromic
2. Cephalometric
a. Lateral ceph
b. Postero-anterior cehalogram
 Others- Hand-wrist radiograph.

25. INTRAORAL RADIOGRAPH
Periapical radiograph Bite-wing
Radiograph

26. EXTRAORAL RADIOGRAPH
OPG

27. PA VIEW OF SKULL

28. FACIAL PHOTOGRAPHS
Uses of facial
photographs:-
1.They are useful in
assessment of facial
symmetry, facial type
and profile.
2.They serve as
diagnostic records.
3.They help in
assessing the progress
of the treatment.

29. EXTRA-ORAL PHOTOGRAPHS

30. INTRA-ORAL PHOTOGRAPHS

31. SUPPLEMENTAL DIAGNOSTIC AIDS

32. SPECIALIZED RADIOGRAPHS

33. a.Cephalometric Radiographs
Uses of cephalometric radiographs
in orthodontics:-
1.It helps in planning treatment for
an individual.
2.Cephalometrics helps in
predicting the growth related
changes and changes associated
with surgical treatment.
3.Cephalometrics is a valuable aid
in research work involving the
cranio-dento facial region.

34. b. Occlusal intraoral films
The following are uses of occlusal
radiographs:-
1.To locate impacted or unerupted
teeth.
2. To locate supernumerary teeth.
3.To locate foreign bodies in the jaws
and stones in
salivary ducts.
4.To diagnose the presence and extent
of fractures.
5. They are useful in orthodontics to
study the effects of arch expansion
procedures.

35. c. Selected lateral jaw views
1.Lateral oblique view is one of the
most enterprising and satisfactory
techniques of having an extraoral
view of the jaw.
Indications:-
a. Unerupted teeth
b. Fracture
c. Pathology
d. Mandibular 3rd molar
e. Periapical area

36. d. Cone shift technique

37.  Also called
1.Tube shift technique
2.Clark’s technique
3. Buccal object rule
4.SLOB technique
The principle states that the object closest to the buccal
surface appears to move in the direction opposite the
movement of the cone or tube head, when compared
with the second film. Object closest to the lingual site
appears to move(on a film) in the same direction that
the cone moved.

38. 2. ELECTROMYOGRAPHIC EXAMINATION
 It is a procedure used for recording the electrical
activity of the muscles.
 Electromyogram is a record obtained by such a
procedure.
 Uses:-
1. In severe Class II division I malocclusion the upper
lip is hypofunctional. Thus during swallowing , the
lower lip extends upwards and forwards to force
the maxilla labially and a strong mentalis activity is
seen. EMG can be used to study such condition.
2. After orthodontic therapy EMG is done to achieve if
muscle balance is achieved.

39. 3.HAND WRIST RADIOGRAPH
 Useful in estimating the skeletal age of a person.
 The hand and wrist region have a number of small
bones whose appearance and progress of
ossification occurs in a predictable sequence.
 This enables a skeletal age of a patient.
 They are useful in assessing growth for planning
growth modification procedures and surgical resective
procedures.

40. 4.ENDOCRINE TESTS
A number of endocrinal disorders , infectious
conditions and metabolic disturbances can
predispose to malocclusion.

41. 5.ESTIMATION OF BMR
 BMR helps in assessment of thyroid function.
 It helps in the calculation of a daily energy
requirement of a person.
 It helps in planning diet for an individual.
 For adult men BMR is 34-37
kcal/squremeter/hour.
 For adult women BMR is
24kcal/squaremeter/hour.

42. 6.DIAGNOSTIC SETUP
 It was first proposed by H.D Kesling.
 The diagnostic set up is made from extra set of
trimmed and polished study models.
 Uses:-
1. It is useful in visualizing and testing the
effect of complex tooth movements and
extractions on the occlusion.
2. The patient can be motivated by simulating
the various corrective procedures on the cast.
3. Tooth size- arch length discrepancies can be
visualized by means of occlusal set up.

43. 7.OCCLUSOGRAM
It is a tracing of a photograph or photocopy of
a dental arch.
It is used for following purposes:-
1.To estimate occlusal relationships
2. To estimate arch length and width
3. To estimate spacing and crowding
4. To estimate anchorage requirements
5. To estimate the tooth movements in
all 3 planes of space

44. RECENT ADVANCES IN DIAGNOSTIC
AIDS

45. XERORADIOGRAPHY
 It is completely dry, non-chemical process that
makes use of the electrostatic process that makes
use of the electrostatic process as in the xerox
machines.
 It was invented by Chester F. Carlson in 1937.
 It makes the use of an aluminium plate that is
coated with a layer of vitreous selenium.
 The selenium particles are given a uniform
elecrostatic charge.

46.  The charged plate is placed in a light-tight, air-
tight cassette.
 When the film is exposed it causes selective
discharge of the selenium depending upon the
amount of radiation used and the relative density
of the object. This pattern of electric discharge
on the plate is called latent image.
 Once the latent image is converted to a real
image on to a paper , the selenium plate can be
discharged, cleaned and used again.
 It can be reused as many as 1000 times.

47.  Advantages;-
1. Cephalometric landmarks are easily identified.
2. Ease of viewing .No special light source is
required.
3. Reduction in exposure time.
4. Ease in manipulation.
5. No need of dark rooms for developing.

49. DIGI GRAPH
 The Digi Graph is a synthesis of video imaging,
computer technology and sonistic digitising.
 The digigraph enables the clinician to perform
non-invasive and non-radiographic cephalometric
analysis.

50. DIGIGRAPH consists of sonic cephalometric device

60.  Two video cameras, permanently aimed and
focused, are mounted on the vertical
column.
 Lighting emanates from sources inside the
boom, thus insuring that all images are
properly illuminated.

61.  According to the manufacturer's information,
one can perform cephalometric analysis and
monitor patient treatment progress as often a
necessary without radiation exposure.

65.  The Digi Graph allows all patient’s models,
radiographs, photographs, cephalograms and
tracings to be stored on one small disc, thereby
reducing storage requirements.
 It is a valuable tool for improving communication
among clinician, patient and staff.

66.  The cephalometric landmarks are digitised by
lightly touching the sonic digitising probe to a
point on the patient’s skin corresponding to it.
 This emits a sound, which then recorded by the
microphone and monitored as X, Y and Z co-
ordinates.

67. Features of Digi graph
 A landmark can be identified as a point in three
dimensions.
 A cephalometric analysis can be made
independently of head position.
 Parallelism of X-ray in mid-sagittal plane and
symmetry of anatomic morphology between left
and right sides is not necessary.

68.  The Digi Graph workstation’s hardware and
software enable the performance of
cephalometric analyses, tracing , superimposition
and VTO.
 The programme is capable of 14 analyses.
 Measurements for any selected analysis can be
displayed on the monitor and the observed
values are shown along with the patient norm
adjusted for age, sex, race and head size
including standard deviations.

69.  Optional components include :
1. A consultation unit: It transports information
in to the operatory, doctor’s office/consultation
area , thus allowing viewing and comparison of
information and development of VTO.
2. A high resolution video camera with a
telephoto lens for taking intraoral views by
framing the video image.

70. 3. A light box for X-rays and a study model
holder for video imaging that will be included in
the floppy disk.
4. Camera and video printer for producing
copies of video monitor information.

72. MRI
 It makes the use of two fundamental properties of
protons, i.e spin and small magnetic movements.
 Advantages:-
1. MRI does not have hazards as it uses non-ionising
electromagnetic radiation.
2. Greater tissue characterisation is possible.
3. Anatomical details are good as in C.T. scan.

73. Disadvantages of MRI
 Time taken is more.
 Not used in patients with cardiac pacemaker.
 Non- visualization of bone makes it useless in
bony lesions.

74. TOMOGRAPHY
 Tomography can be conventional or computed
tomography.
 Conventional-
It is a process by which a layer of an image with
in the body is produced while the images of
structures above and below that layer are made
invisible by blurring.
Computed –
It is also called C.T. Or CAT –These are mainly
complex imaging systems which use thin beams of
X-ray that move in a synchronous manner with an
array of detectors which calculate and attenuate the
X ray beams at different angles and in different
planes.

77. DIGITAL SUBSTRACTION RADIOGRAPHY
 This is an image enhancement method that
removes the structured noise from the images.
 The result is the area of change clearly displayed
either against a neutral grey background .
 The digital substraction technique selectively
enhances the differences between two imges.
 It is impossible to achieve perfect registration of
images during registration .

79. LASER HOLOGRAPHY
 Holography is a photographic technique for
recording and reconstructing images in such a
way that the 3D aspect of an object can be
obtained.
 The recorded image is called a hologram.
 Laser is light amplification by stimulated emission
of radiation.
 Application-
1. Storage of study model images
2. To study the effect of maxillary expansion of
facial skeletons.

81. CINERADIOGRAPHY
 This is basically a radiographic motion picture.
 The subject is oriented properly and stabilized in
a modified cephalostat.
 This diagnostic aid is used to visualize the
swallowing pattern of the patient.
 The X- ray motion picture is studied using a
movie projector.

83. TECHNETIUM SCAN
 It is usually recommended in cases of abnormally
growing facial bones, the commonest condition
being unilateral condylar hyperplasia.
 It is indicated in condylar hyperplasias to confirm
the activity of the condylar active growth site.
 Technetium scan also be useful in skeletal class
III cases to confirm the cessation of the active
growth before undertaking orthognathic surgery.

84. Unilateral condylar hyperplasia

85. CBCT
 The first Cone-Beam Computed Tomography
(CBCT) scanner was used in the Mayo Clinic, USA
for performing angiography in 1982.
 Advantages:-
1. Lower radiation exposure.
2. Reduced scan time
3. Lower cost than CT scan
Disadvantages;-
1. Limited information on soft tissue structures
2. Lower contrast resolution –less discrimination
between different tissue types.

87. PRINCIPLE OF CBCT

88. Applications of CBCT in orthodontics
 Assessment of an impacted teeth e.g.
canines(including evaluation of resorption of an
adjacent tooth)
 For assessment and planning of orthognathic
surgery
 Assessment of cleft palate.

89. Contraindication of CBCT
 Caries detection
 Routine method of assessing periodontal bone
support
 Periapical pathosis
 Demonstration of root canal anatomy

90. STEREOPHOTOGRAMMETRY(3D
FACIAL PHOTOGRAPHS)
 Soft tissue facial analysis
 Evaluation of the craniofacial growth and
development
 Measurement of esthetic facial parameters
Photos-light ; Gramma-to draw; Metron-to measure
It involves photographing a 3D object from two
different co-planar views in order to derive a 3D
reconstruction of the images.
Stereophotogrammetry refers to the special case where
two cameras, configured as a stereo pair , are used to
recover 3D distances of features on the surface of the
face by means of triangulation .
Uses;-

94. SURE SMILE TECHNOLOGY
 It can substantially reduce many common errors
in fixed appliance treatment, and it can enhance
the quality of care afforded to the patient by
compressing the treatment cycle and reducing
the number of appointments.
 Sure smile gives the clinician powerful tools to
deliver consistent, high quality care to all
patients, regardless of practice volume.
 In short,this technology is designed for the
patient-centered practice.

96. PHOTOCEPHALOMETRY
 Thomas in 1978 developed photocephalometry to
better visualize the soft tissues of patient.
 Three radio-opaque metallic markers with holes are
placed on patient’s skin with adhesives and standard
lateral and anteroposterior cehalograms are taken.
 Using the same position lateral and frontal
photographs are taken.
 The photographs are printed to the same size as the
radiographs and are superimposed over the
radiographic tracing taking the metallic markers as
the guide.

99. CONCLUSION
 A thorough knowledge of the clinician about the
disease and along with diagnostic aids will help
the orthodontic diagnosis and treatment
successful . No doubt in it.

100. REFERENCES
 Contemporary Orthodontics . William R. Proffit.
Sixth edition.
 Diagnosis and management of malocclusion and
Dentofacial Deformities. OP kharbanda.2nd
edition.
 Orthodontic Principles and Practice.Phulari.2nd
edition.
 Text Book Of Orthodontics. Gurkeet Singh.3rd
edition.
 Color Atlas of Orthodontic diagnosis.Thomas
Rakosi.

101.  Holograms in orthodontics:A universal sysyem
for the production , development, and
illumination of holograms for the storage and
analysis of dental casts.Romeo. AJODO.Oct
1995;Vol 108 (4):443-7.
 Radiographic exposure conditions and resultant
skin doses in application of xeroradiography to
the orthodontic diagnosis. Nakasima et al.
AJODO. Dec 1980;646-56.
 Digital revolution in orthodontic diagnosis.Annals
of Geriatric Education and Medical sciences. July-
Dec 2017;Vol 4(2):38-40.