STRANG: “There is nothing
complicated about making a diagnosis
in orthodontia, for the moment one has
detected a deviation from normal
occlusion and so determines that there
is malocclusion, the diagnosis is
ANGLE: Normal occlusion, favorable
function& acceptable dentofacial
esthetics represented an identity.
This process could be called the
CASE,HELLMAN &SIMON: Orthodontic
diagnosis required a deeper understanding
of the orthodontic problem. The concepts of
dental and skeletal problem can be credited
to these men. RATIONAL APPROACH
MOORREES & GRON: Dental, skeletal,
muscular factors and the somatic and
emotional development of an individual.
They also considered personal and societal
factors. This view is called the OVERALL
THOMAS RAKOSI: The recognition
and systematic designation of
anomalies, the practical synthesis of
the findings, permitting therapy to
be planned and indication to be
determined, thereby enabling the
doctor to act.
Orthodontic diagnosis requires a
broad overview of the patient’s
RECOGNISING THE PROBLEM
FORMULATING THE PROBLEM
CARRYING THE NECESSARY EXAMINATIONS
INTERPRETATION OF THE RESULTS
Orthodontic diagnosis should be
routinely based on various methods
DIAGNOSIS should be a summary
of the most important facts and
should not take insignificant
secondary symptoms into account.
be referred to
as a diagnostic
Recognize the various characteristics of
malocclusion and dentofacial deformity.
Define the nature of the problem
including the etiology if possible.
Design a treatment strategy based on
specific needs and desires of the
Present the treatment strategy to the
patient in such a way that the patient
fully understands the ramifications of the
PROBLEM ORIENTED APPROACHDIAGNOSIS
EMG activity of
AGE & DATE OF BIRTH
ADDRESS & OCCUPATION
Tetracycline stains on teeth
Viral infection and cleft formation
INTRAUTERINE MOULDING :Pressure
during fetal growth distorts the
developing face. e.g. PIERRE ROBIN
Fibroids of the mother
Metabolic differences: “Cephalometric
study of children with various endocrine
diseases” A.J.O 59:362-375 1971.These
appear to be unlikely causes. (SPEIGER
Injury to the mother
Drug induced deformities: Thalidomide
injuries of the
Mandibular growth retardation.
VOGELGESICHT: Inhibited growth of the
mandible due to ankylosis of the T.M.J
Delivery induced deformation of the upper
POST NATAL HISTORY
Type of feeding: Breast, Bottle
Advantageous: Activates jaw
the physiologic retruded jaw
position at birth.
The child's sucking reflex is
satisfied. Fewer chances of habits.
NON SOLID:TEMPORALIS CHEWER
Minimal abrasion of
1st molars unstable
Lower arch not
HABITS: Duration, frequency &
intensity. Duration is the most imp.
TRAUMA:# of the condyle.
PRIMARY FAILURE OF ERUPTION:
Lead to posterior open bite.
POSTURE: Head: Forward, Chin
extended associated with a long face.
Head backward: Short face
Extensive scar formation
Recorded in pt’s. Own words.
Mention what the pt. feels he/she is
What is important for the patient.
Why has the pt. come?
Esthetics or impaired function.
Reveal systemic ds.
Epileptic pt. takes dilantin
Steroids: decreases resistance to
infection-difficulty in tolerating
Osteoporosis: resorption inhibiting
drugs (prostaglandin inhibitors)
Latex sensitivity: gloves, elastics
Nickel sensitivity: wires &
brackets. If sensitive titanium
brackets or ceramic brackets
may be used.
Past dental history will help in
assessing the pts. or parents
Indicator of pt’s susceptibility
towards Pdl. ds. or caries.
H/O traumatic injury to teeth:
orthodontic treatment exacerbate
periapical symptoms that are
Dental health awareness
Social & behavioral history.
Difficult to obtain;
Parent is reluctant to speak.
Emotional problems are suspected
when :Thumb sucking, poor
progress in school, sleep
walking in a young child,
enuresis in an older child.
To know about learning disability.
Pts have short attention span
To much of detailed information
about treatment can produce
Reduce responsibility of the patient.
EXTERNAL OR INTERNAL
External: supplied by pressure by another
Internal: comes from within based on his
or her own assessment of the situation.
A child or an adult who feels that the
treatment is being done for him will be a
more receptive patient than one who feels
that the treatment is being done to him.
HIGH, MODERATE, LOW
What patient expects from
treatment is related to the type of
If the patient expects social
adjustment problems to be solved
after treatment then he or she is a
poor candidate for orthodontic
Problem with the child than the
Factors important are:
The extent to which the child sees
the treatment as benefit as opposed
to something else he or she is
required to undergo.
The degree of parental control. A
rebellious child with ineffective
parents is likely to become a
FAMILY / GENETIC HISTORY
Any siblings of the patient require
any orthodontic treatment.
Parents ever underwent orthodontic
The tissues primarily affected are:
TEETH: Size, shape , number,
mineralization, path of eruption,
position of tooth germ, sequence of
SIZE: Hereditary micrognathia or
SHAPE: Asymmetries – Crouzon’s
disease, cleidocranial dysostosis.
Class 2 div.2,Mand.prog.,bimax.
protrusion, skeletal open bite,
skeletal mand. retrognathism.
Anomalies of the frena
GENERAL PHYSICAL DEVELOPMENT
To assess the amt. of growth that
has occurred & the potential of
future growth that remains.
Best results-good growers-amt.,
rate, direction, pattern that
Modifiability of a problem &
treatment prognosis are strongly
influenced by growth.
PHYSICAL GROWTH EVALUATION
Whether the child has recently
Whether there is a change in the
size of the clothes?
Whether there are signs of sexual
Whether there is a change in the
GENERAL BODY TYPE(PHYSIQUE)
ASTHETIC: Thin physique, possess
narrow dental arches.
PLETORIC: Obese, have large
square dental arches.
ATHLETIC: Normally built, being
neither thin nor obese. Have normal
sized dental arches.
ECTOMORPHIC: Tall & thin
physique. Grow more slowly &
reach the pubertal growth spurt
ENDOMORPHIC: Short & obese.
HEIGHT & WEIGHT
Clue to the physical growth
It is the way the person walks.
Abnormalities of gait are associated
with neuromuscular disorders.
Poor postural conditions either
lead to malocclusion or
A stoop shouldered child with
the head hung, chin rests on the
chest: Mandibular retrusion.
The shape of the
head is assessed.
MARTIN & SALLER
Long & narrow head.
Based on anthropometric
determination of the max. width of
the head and max. length.
Cephalic index: Max. skull width
Max. skull length
deformity of the
skull in rickets
caused by the
of the frontal
Used to study growth.
Involves measurement of the skulls
found amongst the human skeletal
Adv: Precise measurement can be
made on dry skulls.
Disadv: The growth study is crosssectional.
“Beauty/esthetics lies in the
eyes of the beholder”
Goal: Detect disproportion.
Done with patient either standing in
a relaxed manner or seated in a
straight chair. The upright position
enables to assume a NHP.
FRONTAL VIEW (FACIAL FORM)
road & short face
Apical base is wide
confined to coronal
Long & narrow
Narrow apical base
in trans. dimen.
should be done
incase of crowding.
Steep mand. Plane.
The width of the
base of the nose
should be approx.
same as the inter
distance, while the
width of the mouth
should be approx.
the distance b/w
Enables measurement of skeletal
dimensions on living patients.
Establishes facial proportion.
Various landmarks established in
the studies of dry skulls are
measured in living individuals by
using soft tissue points overlying
the bony landmarks.
Measurement made with st. or bow
Allows to follow
the growth of an
making the same
repeatedly at diff.
general pattern of
FARKAS ANTHROPOMETRIC STUDY
Dentoalveolar midline shift in the upper
The contat of the upper CI does not
coincide with the center of the philtrum.
MIDLINE SHIFT IN THE LOWER
Dentoalveolar: Results from tooth
The mental spine of the mandible coincides
with the midsagittal plane of the skull only
contact pt. of the incisors is deviated.
SKELETAL DEVIATION OF THE
The skeletal midline of the mandible
& the contact pt. of the lower
incisors is deviated.
“Poor man’s cephalometric analysis”
Goals: To establish whether the jaws
are placed proportionately in the
anteroposterior plane of space.
2 lines are drawn: one from the bridge of
the nose to the base of the upper lip &
the 2nd one extending from that pt.
downward to the chin. These line
segments should form a straight line.
Angle: CONVEX PROFILE: Skeletal
CONCAVE PROFILE: Skeletal class 3
DIVERGENCE OF FACE
Defined as an anterior or posterior
inclination of the lower face relative to the
Profile: straight: does not matter whether
it slopes anteriorly (anterior
divergence) or posteriorly (posterior
Divergence does not indicate facial or
dental disproportion whereas profile
concavity or convexity does indicate
disproportion, but does not by itself
indicate which jaw is at fault.
EVALUATION OF LIP POSTURE
Teeth protrude: The lips are prominent &
The lips are separated at rest by more than
Excessive protrusion: Revealed by
prominent lips that are separated when
relaxed, so that the pt. must strain to bring
the lips together, RETRACTION of the
teeth alone tend to improve lip function &
But if the lips are prominent & close over
the teeth without strain, the lip posture is
largely independent of tooth position. In
these individuals retracting the incisors
would have little effect on the lip function.
The lip posture &
prominence should be
evaluated by viewing
the profile with the
pts. lip relaxed.
The upper lip is
related to a true
vertical line passing
through the soft tissue
pt. A & the lower lip is
related to a true
vertical line passing
through the soft tissue
lips fall forward from the line-PROMINENT
Lips fall backward from the lineRETRUSIVE
Both lips are prominent & incompetentAnterior teeth are protrusive.
EVALUATION OF THE VERTICAL FACIAL
PROPORTION & THE MANDIBULAR PLANE
A well proportioned face can be
divided into vertical thirds. This is
called as the LAW OF THIRDS
INCLINATION OF THE MANDIBULAR
Steep: open bite,
long ant. facial ht.
Flat: Deep bite,
short ant. facial
placing a finger or
a mirror handle
along the lower
SANDLER & MURRAY “ Clinical
photography in orthodontics”
EXTRA ORAL VIEWS- FRONTAL
The camera should
the facial midline
plane: skin nasion to
the subnasal pt.
plane: parallel to the
through the stomion.
Mild degree of
asymmetry occurs b/w
the 2 sides of the face.
FRONTAL DYNAMIC SMILE
amount of incisor
& gingival display
while the pt.
Reduction of large
the pts. smile.
CLOSE UP IMAGE OF POSED SMILE
For the analysis of
THREE QUARTER EXTRA ORAL
VIEW- 45 DEGREE PHOTOGRAPH
the way the pts.
Face is viewed
Helpful since the
profile of the pt.
can change during
CLASSIFICATION OF THE FACIAL
Eye ear plane
JAW PROFILE FIELD: Lies b/w both
Ideal average value face: the
subnasal pt. touches the skin nasion
The soft tissue chin point: lies in the
center of the “jaw profile field”. It is
the most ventral point of the soft
tissue part of the chin.
The skin gnathion (the most inferior
chin pt.) lies on the orbital pointer.
NINE POSSIBLE PROFILE VARIANTSA.M SCHWARZ –ST. JAW PROFILE
Average face: The subnasale lying on the
skin nasion perpendicular.
Anteface: Subnasale lying in front of the
skin nasion perpendicular.
Retroface: Subnasale lying behind the skin
BACKWARD SLANTING PROFILE
The soft tissue pogonion is displaced too far
posteriorly relative to the subnasal point.
Backward slanting average face
Backward slanting anteface
Backward slanting retroface.
FORWARD SLANTING PROFILE
The soft tissue of the chin is too far anterior
in relation to the subnasal pt.
Forward slanting average face
Forward slanting anteface
Forward slanting retroface
Use of stereophotogrammetry was first
reported by Thalmaan-degen in 1964.
It involves photographing a three
dimensional object from 2 different
coplanar views in order to derive a 3
dimensional reconstruction of an image.
The landmarks are identified in 3
dimensions to allow tracking of relative
changes in the location of the landmarks as
a result of growth, development,
mandibular movement, injury, skeletal
malformation & treatment.
Captures the human face well.
A 3 dimensional X-ray stereometry is
produced from paired coplanar images in
order to allow accurate merging of 3
dimensional coordinate data from head
films, study casts & facial photographs.
Two photographs are taken with 2 semimetric cameras, which form a
STEREOPAIR. The cameras are mounted
on a frame with a dist. Of 50cm b/w
them,& positioned convergently with an
angle of 15 degrees. With the use of a
analytical plotter & a stereopair a 3
dimensional image of an object is created.
By combining X-rays with the principles of
stereophotogrammetry changes in the bone
density can be tracked in 2 dimensions.
Gives a good impression of the surface of
for quantifying facial asymmetry in
3 dimensions using stereophotogrammetry”
Angle orthod. Vol.65 No.3 1995
Is a 3 dimensional method to quantify facial
morphology for the purpose of diagnosis.
Detect changes in the facial morphology
during growth & development.
Assessing facial contour, surface
appearance of the face.
Evaluation of treatment results.
Quantitative data on facial proportions &
The life like 3D model of the pt. can be
rotated enlarged, measured in 3
as required for
Uses grid projections during exposure
resulting in standardized contour lines on
It is a light scanning technique for three
dimensional facial measurement, in which
telecentric lences are used to eliminate
Suited for smoothly contoured surfaces.
Used as an alternative to
stereophotogrammetry for three
dimensional facial measurement.
Records the shape
of the face.
Changes due to
To study changes
encountered if a
surface has sharp
Great care is
head since small
change in the head
position produces a
large change in the
SOFT TISSUE EXAMINTION
Lips & cheek frenal
Palatal & oral mucosa
The ht. of the forehead (dist. From hairline
to glabella) should be 1/3rd of the entire face
ht.& is as long as the midthird (dist. of the
glabella to the subnasal line)& the lower
third (dist. From subnasale to menton.
Relationship of the forehead is considered
to the bizygomatic width. It can be
described as Narrow or wide.
The lateral forehead contour or the slope of
the forehead could be Flat, protruding,
steep. The dental bases are more
prognathic than incases with a flat
Nasal growth & its
contribution to profile.
Can be in both vertical & anteroposterior projection. More in
Males>Females-10-16 yrs. The
center of this spurt at the age of
Females-spurt for nasal growth12yrs.
Genecov et al “Development of nose & soft
tissue profile” Angle orthod 60(8)191,1990
Nasal projection in females remains virtually
constant from age 12.Thus a orthodontist
evaluating a pt. of class 2 at this age could
expect only a reasonable increase in the
nasal projection. There is a sharp peak in the
nasal tip projection b/w ages 9&10
Nasal projection in males continued from
ages 12-17yrs.Thus any procedure that
results in upper lip retraction in combination
with anterior nasal growth would produce
less than optimal relationship b/w the lips &
SIZE OF THE NOSE
The vertical nasal length measures 1/3rd of
the total facial ht. (dist. From hairline to
The relationship b/w vertical & horizontal
length of the nose is 2:1.
Microhinic type: The root of the nose is
high, short nasal bridge & an elevated tip.
Straight, convex, crooked
SHAPE & WIDTH
Should be assessed
since they indicate
impairment of nasal
Nostrils: oval &
COMPETENT: Slight contact of the lips
when the musculature is relaxed.
Up to 4mm of lip separation is normal
especially in young children.
Is defined as the inability to seal the lips without
Anatomically short upper lip which do not contact
when the musculature is relaxed.
Lip seal is achieved after active contraction of
orbicularis oris & mentalis muscle
Vig & Cohen “Vertical growth of the
lips, A serial cephalometric study”
A.J.O 75:405 1979
Both upper & lower lip grew more
than the skeletal lower face.
The lower lip grew vertically more
than the upper lip.
Most children exhibited lip
incompetence at age 6-8 yrs. This is
due to incomplete soft tissue growth
& should be considered normal.
POTENTIALLY INCOMPETENT EVERTED LIPS
Lip seal is
prevented due to
tissue & weak
VERTICAL LIP RELATIONSHIP
In a balanced face the length of the
upper lip measures 1/3rd the lower
lip & the chin 2/3rd of the lower face
The upper incisal edge exposure with
the upper lip at rest should be
It is important to distinguish
excessive exposure of teeth caused
by over eruption of the incisors from
that caused by underdevelopment of
the upper lip.
Positive lip step: Protrusion of the
lower lip in relation to the upper lip.
Seen in class 3 malocclusion.
NORMAL LIP PROFILE
Slightly negative lip profile. The
lower lip slightly behind the upper
NEGATIVE LIP STEP
Marked retrusion of the lower lip as
a symptom of class 2 malocclusion.
MAMANDRAS “Linear changes of the
maxillary & mandibular lips” A.J.O
Max. lip length in females-14yrs.The
mand. vertical lip length growth
-16yrs.They attained the max. Lip
thickness by age 14 followed by
Males attained max lip length-18yrs,it
was not complete. Max lip thickness
was attained by 16yrs.
Thus the effect of extraction therapy
would be more noticeable in females
with straight or convex profile than in
Formed b/w a tangent to the lower border
of the nose & a line joining the subnasale
with the tip of the upper lip. (Labrale
Reduces: max. prog., proclined ant.
Obtuse: Retrognathic maxilla
The bone structure
Thickness & tone of the mentalis
Morphology & craniofacial relation of
Recessive, adequate or
The mentalis muscle becomes
Seen in class 2 div 1 cases where
puckering of the chin may be seen.
It is the concavity
present below the
OVER DEVELOPMENT OF THE CHIN
HT. (Mentolabial sulcus to menton)
Lip closure is difficult in this type of facial
Hyperactivity of the mentalis muscle
Genioplasty required to change the
insertion of the mentalis muscle.
CHIN FORMATION & PROFILE
Protruded chin, marked mentolabial
sulcus – retruded lip profile.
Negative chin, absence of the mentolabial
sulcus causing a protruded lip profile.
ASYMMETRY OF THE CHIN:MIDLINE
OF THE MANDIBLE
Rotation of the entire mandible to the left
side- MANDIBULAR LATEROGNATHY
Placement of the chin on to the left side.
Small, Long &
Long tongue: Tip
of the nose.
Class3:Broad ,low lying
Imprints of the teeth on the lateral margins
of the tongue indicate a discrepancy b/w
the width of the dental arch & width of the
tongue. Size of the oral cavity should not
be decreased further by ortho treat.
Tongue tie-can lead to impaired tongue
The tongue lies low.
Only indicated when the attachment is inserted
deeply with the fibre inserted into the interdental
Done after the eruption incisors.
X ray shows a bony fissure b/w the roots of upper
BLANCH TEST: Upper lip is held away - pull is
exerted on the frenum-Area around the incisive
papilla becomes blanched.
MANDIBULAR LABIAL FRENUM
Broad insertion which exerts a strong pull
on the FREE & ATTACHED GINGIVA can
lead to gingival recession.
Thick fibrous or
THIN FRAGILE GINGIVA
Alv. Process is narrow
Roots can be palpated
through the mucosa.
develop around the
Visible vascular pattern
of mucous membrane
Increased tendency of
the tissue to produce
periodontal damage by
OCCLUSAL TRAUMA LINGUAL RECESSIONS
relation b/w the
tip of the tongue &
the lower incisors.
Palatal depth & shape varies in
accordance with the facial form.
Brachycephalic pt.- have broad &
Rugae can be used as a diagnostic
criteria for ant. proclination. Third
rugae can be seen in line with the
Traumatic deep bite class2 div 1
Groove in the palatal
mucosa caused by the
lower anterior teeth
due to long standing
Scarred palate after
surgical closure of an
isolated palatal cleft.
No. of teeth present, unerupted,
The counting must include not only
the teeth seen but those developing
or not developing within the jaws.
Girls develop teeth earlier than
Balanced relationship b/w the width of the
dental arches & transverse development of
the apical bases.
Tangents along the outer surfaces of
posterior teeth are parallel to each other.
DISHARMONY IN WIDTH OF APICAL BASE &
MAX. DENTAL ARCH (APICAL CROWDING)
Upper post. teeth are tilted buccally in comparison
to their apical base.
Cranially convergent tangents of the posterior
buccal tooth surface imply that the basal bone is
smaller than the dental arch.
Expansion of the dental arch is contraindicated.
BROAD APICAL BASE
The apical base is wider than the dental arch & the
posterior teeth are tipped lingually. Discrepancy is
indicated by interdental spacing.
The tangents of the post. buccal surfaces converge
Expansion therapy is indicated.
Orthodontic treatment is
contraindicated when carious teeth
There is reduced enamel resistance
which is a contraindication for fixed
Occlusal abrasions are a result of
attrition & indicative of
The anteroposterior relationship of the
maxillary and mandibular molars is correct,
with the mesiobuccal cusp of the maxillary
1st molar occluding in the mesiobuccal
groove of the mandibular 1st molar.
CLASS - 2
The lower dental arch is in a distal
relationship to the upper dental arch. The
mesiobuccal groove of the mandibular 1st
molar contacts the distobuccal cusp of the
maxillary 1st molar
CLASS - 3
The mandibular 1st molar is mesial to the
maxillary 1st molar and the mandibular
incisors are in anterior crossbite.
The vertical overlap 0f
the maxillary incisors
over the mandibular
incisors is termed as
The maxillary and the
should be in contact in
order to prevent supra
eruption of the
VARIATIONS IN THE BITE - DEEP
CLOSED BITE: Due to premature
loss of posteriors.
OVERJET- MEAN VALUE-2mm
Is the term used to
express the horizontal
distance between the
most labial surface of
the mand. Incisor and
the incisal edge of the
Equal to the labio
lingual thickness of the
max. incisor edge.
Sensitive to abnormal
lip and tongue function.
Variations are due to
abnormal position of
either upper or lower
CURVE OF SPEE
It refers to the
curvature of the
beginning at the tip of
the lower cuspid &
following cusp tip of
bicuspids & molars
continuing as an arc
through the condyle.
Results in the alignment
of teeth to offer max.
resistance to functional
restricts the amt.
space available for
the upper teeth.
excessive space in
the upper jaw.
An abnormal relationship of one or more teeth to
one or more teeth of the opposite arch ,in the
buccolingual or labiolingual direction.
Can be dental or skeletal.
Can be either unilateral or bilateral.
TRANSVERSE OCCLUSAL DEVIATIONS
OF THE POSTERIOR SEGMENT
INTRA ARCH DISCREPANCY
Occlusal view of the orthodontic casts:
crowding, spacing & rotation.
“Arch width and form” A.J.O
1999:115:305-313 Robert et al:
Male arches grow wider than female.
Lower intercanine width does not increase
Little changes occur in the premolar arch
width after the age of 12.
The upper & lower intermolar width
increases to a considerable extent b/w ages
7 & 18.
can be applicable to a
growing child. There is no evidence
that appliance can stimulate growth
beyond that which would occur
Arch expansion is more stable in the
absence of extractions & is most
effective in the posterior region. There
is unlikely to be stable expansion in the
lower intercanine width unless the
canines are displaced lingually.
Expansions of the arches posteriorly
can be achieved more readily where
anteroposterior movement of the
arches take place.
VISUAL TREATMENT OBJECTIVE
Can give an excellent clue whether any
functional appliance that postures the
mandible forward would improve the
facial appearance & the profile.
The patient is asked to to posture the
mandible forward into a correct sagittal
Profile improves-motivates the pt. to
achieve a treatment goal.
Not improved-other forms of treatment
Indicated in: Functinal retrusion,
deep overbites excessive
interocclusal clearances with a
normally positioned maxilla.
V.T.O: manually or cephalometric
Tracing represents the changes
expected or desired during
In a child the V.T.O would have to
incorporate the expected growth,
any growth changes induced during
treatment & any repositioning of
teeth expected from orthodontic
Replica of the
Serves as an
reference as the
Measures progressAids in pt. motivation
Occupy large amt. of
Liable to damage
during storage &
Difficult to discuss a
particular case over
Holography uses laser light to reproduce
a very high quality, three dimensional
image of the cast. The recorded image is
called a HOLOGRAM.
The first hologram was produced by
LEITH & UPATNIEKS in 1964.
They permit three dimensional model
analysis, superimpositions & storage.
HOLOGRAPHIC VIEWS: Frontal,
occlusal,Rt. buccal & left buccal.
Holograms in orthodontics: A.J.O Oct
Holocamera: easy to
handle. The model
being photographed is
placed on glass plate
The laser beam used
in the camera is
Developed to expose
Consists of series of
trays that contain the
various chemicals used,
a mechanical engine
that controls the
movements of the
holder in which plates
can be placed.
30 plates can be
The holder carries the
plate from tray to tray
each having a different
lamp: to illuminate
Plate holder mounted
on an x-y-z
positioner. The z
micropositioner has an
optical fiber which is
connected to a laser
diode that projects a
small red spot light
used for depth
Measurement of incisor intrusion.
Study the effects of high pull headgear.
Tooth position measurements.
Study the effect of max. expansion on
Study the effect of class2 elastics on bone
Study the effect of cervical headgear on
Facial & dental arch symmetry.
Determine the centre of rotation produced
by orthodontic forces.
Lower incisor space analysis.
Convenient, low bulk
Resistant to almost all destructive agents apart
from fire. These films may be scratched or bent or
covered in dust without interfering with the latent
Superimposition of images is possible, thus
detection of any changes & tooth movement are
Holographic image can be measured in 3
Ease in storage, transportation
Cost similar to conventional photography.
Inability to place the holograms
immediately next to the patient’s
mouth to make side by side
Cannot be adjusted once made.
Incorrect occlusion of the models
when the holograms are being
Involves positive-print 1:1 photographs of
dental casts. The tracings of these
photographs are called as occlusograms.
These are actual size photographs of the
occlusal surface of the dental cast.
Developed by C.J BURSTONE in 1961.
Thus combining occlusograms &
cephalometric head films it now possible to
make treatment discussions in all three
planes of space.
TECHNIQUES: Photographic &
4 into 5 inch box camera mounted on a sliding
rack so that the distance from the track is
registration track on the oclusostat for the
placement of the cast.
The occlusal surfaces of the teeth are flush with
the leading edge of the oclusostat which is also
the focal length of the camera.
The recommended focal length of
the camera:210mm & can be stopped
down to f:45 for the best depth of
The dist. from the leading edge of the
occlusostat to the camera lens &
from the camera lens to the film is
abt.42cm.At these settings no
enlargement is found.
Exposure time:5-30 secs. depending
on the lighting (incandescent to
florescent) & the film can be
processed with X-ray developer &
The occlusal surfaces of the upper & lower dental
casts are photographed in a 1:1 ratio & a tracing is
made using the photographs.
4 into 5 inch positive film transparencies are ideal.
These transparencies allow the occlusograms to be
held one over the other to examine cuspal relations.
However for treatment planning purpose tracings
are still required.
These photographs can be taken either with a
35mm camera & enlarged to a 1: 1 magnification or
with a 4 into 5 inch Polaroid camera for 1:1 instant
photographic prints. Photographic prints are ideal for
tracing purposes. One problem with these positive
film traspararencies is the maintenance of the
accurate orientation of the dental cast, which needs
to be trimmed in the centric relation position
Impressions are made-casts are poured &
The posterior borders are trimmed
perpendicular to the occlusal plane & the
palatal midline. They are in flush with
each other when the casts are in C.R. The
bases are parallel to the occlusal plane.
Wax jaw registration is made with the
mandible in most retruded position,
recording the occlusal surfaces without
perforating the wax.
For lateral orientation each cast has an
extended registration groove.
The casts are then finished & polished.
For the occlusogram tracing acetate paper with the
rough side up is placed over the occlusograms & the
max. & mand. teeth are outlined ,showing the
gingival tooth contour, incisal edges, buccal cusp
ridges, central grooves & cusp tips, the upper &
lower registration lines, mid sagittal reference line
based on the mid palatal raphe & incisive papilla.
“R” & “L” should be marked on the right & left sides
to avoid confusion.
The study models are prepared as
With models in the centric relation & teeth
in occlusion three marks on each model
are made. i.e. on the rt. & lt. side of the
buccal segment & in the midline.
The casts are then photocopied on a
Xerox machine & the occlusal photocopy
is used to obtain a tracing.
Determine arch form & width.
Arch length discrepancies (crowding or spacing).
To estimate occlusal relationships.
To estimate tooth movements in all three planes.
Anchorage requirements in each quadrant for
The presence & extent of skeletal asymmetries.
Presence & extent of tooth mass discrepancies.
Determines changes in the cant of occlusal plane.
Aid in arch wire construction.
Growth changes in the arch can be seen with the
help of the tracings.
Quantifying treatment progress.
Not very accurate.
Possibility of using a occlusogram
with a head film produces difference
To overcome this a user friendly
software was developed…………!
3-D OCCLUSOGRAM SOFTWARE
A.J.O Sept. 1999
The procedure includes :
Image scanning & setting.
Occlusal view processing
Lateral cephalometric processing
Combination of lateral cephalometric image
with the occlusal views of the upper & lower
dental casts complete the 3 dimensional set
up of the patient.
Demonstrates all the treatment
possibilities. All the needed movements of
the teeth are clearly visible on the occlusal
views in the 3 planes of space allowing the
design for the “custom made appliance” &
the lateral cephalogram shows the planned
displacement for the molars & the incisors.
The software can simulate the results of
standard surgical procedures.
Ease in using
Accurate & precise
e-MODELS-3D Digital dental models using
laser technology- J.C.O (2)-2003
Three dimensional digital study model.
Methods of producing digital models:
Destructive imaging: Removes the part
of the cast ,a little at a time ,while it is
Non destructive imaging: Uses
structural light ,laser light or x-rays to
image while leaving the original cast
e - models: are
constructed through a
laser scanning process
that digitally maps the
geometry of a patient’s
dental anatomy to a
high resolution 3D
digital image with an
accuracy of .+ 01mm.A
laser stripe is projected
onto the surface of the
plaster cast & a digital
camera is used to
analyze distortions in
the stripe. The plaster
cast is oriented on all
axes to expose all its
surfaces for scanning.
This process produces 3D vertices
that are connected into thousands
of triangles to form the 3D image.
The software then displays the emodel on the computer screen by
assigning color shades to each
triangle based on its relative
orientation to a digital light source.
This results in a high-resolution 3D
image that can be viewed measured
& manipulated on the computer
screen as if the cast is in your hand.
ADVANTAGES OF e-model
Measurements can be made in any plane or
Various analysis such as Bolton’s analysis, arch
width & length analysis can be done.
Cross-sectional tools allow e-models to be sliced in
any vertical or horizontal plane to check symmetry,
overjet, overbite & complete measurements at any
Permits analysis of occlusal relationships.
Improves accuracy & efficiency of orthodontic
diagnosis, treatment planning & bracket placement.
Midline analysis (skeletal or dental asymmetries can
Mock surgeries & presurgical evaluation can be
Ease in storage
Latest innovation in 3D
treatment options to help
determine the most
effective treatment plan.
Enables the clinician to
simulate tooth rotations
,movements & extractions
with a click of the mouse.
They allow pts. to watch
the movement of their own
teeth from a malocclusion
view to a post treatment
tool for pts., their families
& referring dentists.
Photocopies of models appear to be valid
Comparing pre & post treatment arch
Checking original tooth rotations
For ease in communication
Producing occlusograms for
For maintaining pt. record.
Adv: Easy to handle & store
precise for measuring arch
Less precise for producing
occlusograms for space analysis
Can produce varying degree of
distortion since the models are 3
dimensional. The distortion can be
limited to 1-2% enlargement.
Is a synthesis of video imaging,
computer technology & three
dimensional sonic digitizing.
It enables the clinician to perform
non invasive & non radiographic
Product of DOLPHIN IMAGING
DIGIGRAPH WORK STATION
Measures about 5 feet into 3 feet into 7 feet.
The main cabinet contains electronic circuitry & the
pt. sits next to the cabinet in an adjustable chair.
The head holder is suspended from a boom,
supported by a vertical column attached to the
cabinet. Two videocameras, permanently armed &
focused are mounted on a vertical column. Light
emanates from sources inside the boom, thus
ensuring all images are properly illuminated.
This device uses sonic digitizing
electronics to record cephalometric
landmarks by lightly touching the
sonic digitizing probe to the pt. skin.
This emits a sound which is then
recorded by a microphone as x, y,z
OPTIONAL COMPONENTS INCLUDE
A consultation unit that transports
information into the operatory, doctors
office or consultation area thus allowing
viewing & comparison of information &
development of visual treatment
2nd high resolution video camera with a
telephoto lens for taking intra oral views
Light box for x-rays & a study model
holder for video imaging.
Camera & video printer for producing
copies of video monitor information.
CAPABILITIES OF THE MACHINE
A landmark can be identified as a
point in three dimensions.
A cephalometric analysis can be
made independent of head position.
Neither parallelism of the x-ray in
the mid sagittal plane nor the
symmetry of anatomic morphology
b/w left & rt. side is necessary.
Perform cephalometric analysis e.g.
Holdaway, Jaraback, Down, Steiner,
Burstone, Tweed, Ricketts
Monitor patient treatment progress
Useful in quantifying facial asymmetries
Allows pts. radiograph, photos& models to
be stored on a small disk thereby
reducing storage requirements.
Valuable tool for improving
communication among clinician patient &
Consistent & reproducible
No radiation exposure
With practice relatively efficient.
3 DIMENSIONAL CONE BEAM
COMPUTERIZED TOMOGRAPHY IN
Computerized tomography was developed
by GODFREY HOUNSFIELD in 1967.
It utilizes conventional x-ray technology &
computerized volumetric reconstruction to
reproduce a three dimensional image.
The object to be evaluated is captured as
the radiation source falls onto a 2
Images may be a full head view, skull view
or regional components.
Produces a more focused beam & less
scatter radiation as compared to the
conventional fan shaped CT devices.
Increases x-ray utilization & reduces the Xray tube capacity.
CBCT ACQUISITION SYSTEMS
To locate ectopic cuspids & to design
treatment strategies that allow minimally
Location of oral abnormalities (oral cysts,
ectopic/ buried teeth & supernumeraries).
Airway & volumetric analysis
Assessment of bone density, dimensions.
quality & alveolar bone height.
Radiation exposure is
less than conventional
CT. It depends upon
the settings used- kVp
Effective dose as low as
45uSv to as high as
Less expensive &
Does not map out
muscle structures &
Does not capture color
texture of the skin.
Long capture time for
the full view of the
movements (nostrils &
breathing) will lead to
inaccuracies in the soft
Orthodontic diagnosis: Thomas Rakosi
Graber Vanarsdall: Orthodontics current
principles & techniques
Athanasios: Orthodontic cephalometry
Proffit: Contemporary orthodontics
Swain: Orthodontics: Current principles &
T.M Graber: Orthodontics principles &