Facial asymmetry

FACIAL ASYMMETRY
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DEFINATION
Facial asymmery is defined as the presence of a clinically
significant variation between the two halves of the face that
the patient (or parents, in the instance of most congenital
asymmetries) is concerned about and that can be quantified by
the clinician.

STRUCTURAL CLASSIFICATION OF DENTOFACIAL
ASYMMETRIES
Asymmetries can be classified according to the structures involved
a.Dental asymmetries a vertical asymmetry-canted occlusion
b.transverse –posterior cross bite
c.anteroposterior- anterior crossbite
b.Skeletal asymmetries: The deviation may involve one bone such as
the maxilla or mandible or it may involve a number of skeletal and
muscular structures on one side of the face, e.g.hemifacial microsomia
Muscular asymmetries: Facial disproportions and midline
discrepancies could be the result of muscular asymmetry
Functional asymmetries: These can result from the mandible being
deflected laterally or antero-posteriorly, if occlusal interferences
prevent proper intercuspation in centric relation

ASYMMETRY CAN BE DESCRIBED AS QUALITATIVE
OR QUANTITATIVE.
a.Quantitative asymmetries. a.Qqualitative asymmetries
includes difference in number includes differences in size
THERE ARE THREE MAIN CAUSES OF FACIAL
ASYMMETRY AND DENTAL MIDLINE IRREGULARITIES:
A. True skeletal asymmetries of the facial structures including the
mandible and/or maxilla
B. Dental asymmetries in one or both arches and
C. Functional shifts of the mandible during closure or opening.

THE POTENTIAL ETIOLOGIES OF ASYMMETRY
GENETIC
A. Hemifacial facial microstomia.
B. Uniteral cleft lip and palate
C. Multiple neuro fibromatosis
.INTRA-UTERINE PRESSURE during pregnancy and significant
pressure in the birth canal during parturition can have observable
effects on the bones of the fetal skull. Molding of the parietal and
facial bones from these pressures can result in facial asymmetry.
These effects are generally transient with rapid restoration of the
normal relationships of the skull within a few weeks to several month

ENVIRONMENTAL FACTORS
a.sucking habits
b.asymmetrical chewing habits caused by dental caries, extractions,
and trauma.
FUNCTIONAL DEVIATION.
Due to any premature contact.
LOCALISED PATHOLOGY
a.Osteochondroma of the mandibular condyle
b.condylar hyoplasia,hyperplasia
c.irradiation
d.lymphangioma
e.fibrous dysplasia etc.
.

TRAUMA OF THE HARD AND SOFT TISSUES. Untreated farcture of condyle
INFECTION AND INFLAMMATORY CONDITION OF TMJ AND OTHER BONY
STRUCTURE
Trauma and infection within thetemporomandibular joint could result
in ankylosis of the condyle to the temporal bone that leads to
unilateral mandibular underdevelopment on the affected side and
damage to a nerve may indirectly lead to asymmetry from the loss of
muscle function and tone.

MUSCLE DYSFUNCTION
Affect the jaw growth in two ways
1.Formation of bone at the point of muscle attachment depends on the
activity of the muscle
2.the musculatute is an important part of the total soft tissue
matrix,whose growth carries the jaws downwards and forwards

A
ESSENTIAL PATIENT EVALUATIONS FOR FACIAL ASYMMETRY
A General patient evaluation
1. Medical History
2. Dental evaluation
a Dental history
b Dental health
B Social-psychologic evaluation
C Esthetic facial evaluation
a Photograph for facial evaluation d.Duration of asymmetry
b Front-face analysis e.Level of asymmetry
c Profile analysis
D Cephalometric evaluation
1. Soft tissue
2. Skeletal relations
3. Dental relations
E Panoramic or full-mouth periapical evaluations

F Occlusal evaluation
A Functional
B Static 1. inter arch
2 .intra arch
3. tooth mass
B.Masticatory muscle and temporomandibular joint evaluation
1. Masticatory muscle
2.Mandibular movements
3 Temporomandibular joint symptoms
4.Temporomandibular joint signs

MEDICAL HISTORY
The patient population seeking treatment for correction of
dentofacial deformities are widely varied in age and generally has
no serious coexisting medical conditions, however Particular
attention must be given to cardiopulmonary endocrine,
hematologic, neurologic and allergic problems in the medical
history. Medical problems in these areas can complicate the
general anesthesia or reconstructive surgery
DENTAL EVALUATION
It includes the history of previous orthodontic, surgical, restorative,
periodontal and prosthodontic treatment.

SOCIAL-PSYCHOLOGIC EVALUATION
The socio-psychologic makeup of patients is often neglected
when correction of facial deformity is considered. Yet the
psychologic makeup of the patient is important because,
despite an objectively favourable treatment result, certain
patient will express dissatisfaction with their results. This can
occur for two basic reasons
(1) unrealistic patient expectations regarding the results of
treatment or
(2) failure of the clinician to inform the patient realistically of the
probable treatment result (especially esthetic).

ESTHETIC FACIAL EVALUATIONThe esthetic facial evaluation is
done directly on the patient, with the patient standing or seated comfortably.
The observe must help the patient maintain a head posture with the
Frankfort horizontal and interpupillary lines parallel to the floor, because
patients with facial deformities commonly exhibit compensatory head
posturing where by the head is tilted slightly to the right or left to minimise
the effect of deformity. In addition, the patient may develop a compensatory
mandibular position hair style or makeup to direct attention away from their
facial asymmetry

THE ESTHETIC FACIAL EVALUATION INCLUDES
A.Photograph B.front face analysis C.Profile analysis
D. Duration E.Level of asymmetry F.Type of deformity
PHOTOGRAPH FOR FACIAL EVALUATION
FRONT FACE FRONT FACE SMILING

RIGHT AND LEFT PROFILE

SUBMENTAL VIEW
The submental view is taken with the patient,
s head hyper
extended about 45 degrees. It is useful to assess symmetry and
projection of the anterior cranial vault, orbital areas and cheeks.
Nasal deformities are also well documented and studied in this
view

SUPERIOR VIEW
The superior view is taken with the patient's head
hyperflexed about 45 degrees. Like the submental view, it is
useful in assessing anterior cranial vault, orbital cheek and nasal
deformities. It is often more useful than the submental view for
demonstrating and diagnosing cheek deformities.

THREE QUARTER FACE VIEWS
Three quarter face views are taken with the patient's head
turned midway (45 degrees) between the front face and profile
view. The primary use of this view is to document and diagnose
facial anomalies associated with the auricular and preauricular
areas, the mandibular angle, the ascending ramus of the
mandible, the nose, and the cheeks.

SYMMETRY VIEW
It permits assessment and documentation of the relation of the
dental midlines to the facial midline and the clinical relevance of
any occlusal plane cant. This photo should be taken with the
patient's interpupillary and Frankfort horizontal plane parallel to
the floor.

FRONT FACE ANALYSIS
Symmetry, balance and morphology are the three major elements that
are important in the production of good front face esthetics
SYMMETRY
A small degree of mild bilateral asymmetry exist in essentially all
normal individual.It can be revealed by comparing the real full
face photograph with composites consisting of two right or two left
Sides. This normal asymmetry usually results from a small size
difference between the two sides

Composites consisting actual composites consisting
of two left sides of two right sides

IDEAL FCIAL PROPORTION
TRANSEVERSE FACIAL PROPORTION
Rule of fifth describe the ideal transverse relationship of the face.
The face is sagittally divided in to five
equal parts from helix to helix of outer
ear.Each of the segments should be one
eye distance in width
ATHE CENTRAL FIFTH OF THE FACE
B- THE MEDIAL TWO FIFTH
C- THE OUTER TWO FITTH

VERTICAL FACIAL RELATION- THE FACIAL ONE THIRDS
A well proportioned face is vertically divided in to equal thirds by horizontal
lines,from hairline to midbrow, midbrow to subnasale,
and subnasale to soft tissue menton The thirds
are within a range of 55 to 65 mm, vertically.
The equality of the middle and the lower thirds
should not be used as the determining factor in
facial height changes. The appearance of the
landmarks (incisor exposure, interlabial gap)
within the lower third are more important in
assessing balance than are the equality of the
middle and the lower thirds.

THE LOWER ONE THIRD
The lips are measured independently in a relaxed position The normal
length of upper lip is measured from subnasale to upper lip inferior
The
lower lip is measured from lower lip superior to soft tissue
menton.During examination the relationship of the lips to the facial
midline,its relationship to incisors during rest,smiling and the inter
labial gap should be noted. The width of the lips from
commissure to commissure is
normally about equal to the inter
Pupillary distance.If asymmetry
exists onemust determine if the
existing asymmetry is primarily the
result of

1.an intrinsic lip deformity, as exists in many patients with
clefts,
2. facial nerve dysfunction, or
3.an underlying dental-skeletal asymmetry.
Each of these conditions requires different treatment
considerations

Facial level To examine facial levels a reliable horizontal landmark
line is necessary. With the patient in natural head posture, the pupils are
used as the horizontal reference line and adjacent structures are
measured relative to this line. Structures compared with the pupil line are
1.upper canine level
2.lower canine level, and
3.chin and jaw level.
Mandibular deviations commonly
have upper and lower occlusal cants
with chin and jaw line canting associated

FACIAL MIDLINE The evaluation of facial asymmetries is initially
carried out by constructing on a front face photograph a line that represents the
patient's true facial midline Midlines are assessed with upper most condylar position
with the teeth in their initial contact position.
If occlusal slides alter joint position, no reliable
midline assessment can be made. The relative
positions of soft tissue landmarks (nasal bridge,
nasal tip, filtrum, chin point) and dental midline
landmarks (upper incisor midline,
lower incisor midline) are noted.. Filtrum is
usually a reliable midline structure and can
be used as the basis for midline assessment
most often

Once the midline is consrtucted, an initial series of eight right and
left measurements are made- bitemporal, lateral canthus, cheek
promenence, preauricular area, alar bases, mandibular angles,
lateral commissures, and parasymphysis area.
COMPARISON OF FACIAL HEIGHT vs WIDTH OF VARIOUS
BILATERAL STRUCTURES
Value or Ratio % TFH
Total Facial Height Tr-Gn
Bitemporal Ft-Ft/Tr-Gn 65
Lateral canthus Ex-Ex/Tr-Gn 55
Cheek Prominence Zy-Zy/Tr-Gn 75
Preauricular area Pa-Pa/Tr-Gn 80
Alar bases Al-Al/Tr-Gn 18f20m
Mandibular angles Go-Go/Tr-Gn 55
Lateral commissures Ch-Ch/Tr-Gn 30
Parasymphysis Ps-Ps/Tr-Gn 30

NOSE
The nose is studied for form and symmetry. When deformities exist in
the nose, their specific anatomic location - glabella, dorsum, tip, or alar bases -
is noted. Normal alar base width should be approximately the as the
intercanthal distance.,which should be the same as the width of the eye.
The significanes of alar width in
orthognathic Surgery is most recognized
in maxillary surgery. Movement of maxilla
in LeFort I osteotomies Often results in
widening of the nasal base,Which in some
cases may be acceptable but in most cases
is not esthetically favourable.

CHEEKS
Evaluation of the cheeks consists of sequential assessment of the
malar eminences, infraorbital rims, and paranasal areas for
symmetry and normal projection.
CHIN
The chin is evaluated for symmetry, vertical relations, and
morphology and its relationship to the mandibular angles and
inferior border of the mandible. Often the chin may be more
tapered or more square than the rest of the face. When such is the
case it must be noted because, though minimal before treatment,
such inconsistency in morphology may become more noticeable
with certain types of treatment (genioplasty), and must be
corrected to achieve optical facial esthetics

DURATION OF ASYMMETRY
It is important, both diagnostically and prognostically, to
determine how long the patient's face has been asymmetric.
When the asymmetry has been present for a long time and its
magnitude has not changed noticeably, the clinician can assume
that the condition is stable and no special growth studies are
necessary. When the asymmetry has been noticed only within
the last few months, it is assumed to be "growing" until proven
otherwise.
DETERMINATION OF THE LEVEL OF THE ASYMMETRY
When a facial asymmetry exists, the clinician must determine the
extent of the asymmetry relative to the facial thirds-upper third,
middle third, lower third, or combinations of these.
A.Lower third face the lower third face asymmetry may
involvethe chin, the mandible, the maxilla or any combination of
the three

MANDIBLE
The most common asymmetric dentofacial deformities involve the
mandible. The chin may contribute to the asymmetry, if it is more
asymmetric than the mandible as a whole or may be
noncontributory when it is no more asymmetric than the
mandible. Mandibular asymmetries are usually accompanied by
dental compensations where the teeth have adapted to the altered
soft-tissue matrix surrounding the asymmetric mandible.
MAXILLA
An isolated asymmetry of the portion of the maxilla with in the
lower third face-the alveolus and associated dentition- is
extremely rare. Most often an isolated maxillary asymmetry is
dental rather than skeletal because of loss of teeth, unless such
asymmetry is due to trauma.

B. MIDDLE THIRD FACE
The most common area of asymmetry in the middle third face is
the nose. These are often development, secondary to trauma, or
secondary to cleft lip and palate. The cheeks and orbits are the
second most common area of midface asymmetry. It is important
not only to determine that cheek asymmetry exists but also to
determine if one side is deficient or the other is excessive.
C. UPPER THIRD FACE
Some dentofacial deforities are accompanied by asymmetries in
the upper third face- the supraorbital rims, forehead, and
temporal regions. Many of those that accompany dentofacial
deformities are amenable to either bone recontouring or
augmentation.

DEFICIENT or EXCESS
After the general location of the asymmetry is determined, the next decision to
be made is whether one side is deficient or the other is excessive..
1.Total width measured is compared with total face height (ratio) to determine
if the dimension in question is too large (excess) or too small (deficiency).
Zy-zy/Tr-Gn x 100=75%
Zy-zy =0.75x facial height
0.75x190=142.5
2. If a deficiency exists, the smaller of the
two halves is judged to be deficient.
3.If an excess exists, the larger of the two
halves is judged to be excessive
7063
190
133

OCCLUSION EVALUATION
A. FUNCTIONAL EVALUATION
The functional evaluation is done to determine the compatibility
between centric occlusion (CO) and centric relation (CR) and to
assess tooth wear. Since many Class II and asymmetric
individuals have "habitual occlusions," the compatibility between
CO and CR must be carefully evaluated. Failure to appreciate
meaningful inconsistency in CO and CR may result in significant
errors in both treatment planning and in surgery.
B. STATIC EVALUATION The static evaluation is performed on
anatomically oriented models and is begun by doing an intraarch
analysis, followed by interarch analysis and a tooth mass
evaluation

INTRAARCH ANALYSIS - MAXILLARY ARCH
Arch should be analysed for both transverse and AP symmetry
Ap reference plane is constructed using mid palatal raphae as a reference
Plane and the tuberosity plane(drawn perpendicular to AP plane) is used as a
transverse reference plane The position of teeth and arch symmetry can
be measured with respect to these plane
Cross section of the second palatal
Rugae
mid point between the paired
foveolae

INTRAARCH ANALYSIS-MANDIBULAR ARCH
consrtuction of mandibular midline is more difficult than maxillary
midline
The anterior point can be precisely
Marked using mental spine film or
by using the lingual frenum
The posterior point is determined by
a perpendicular,which runs from the
posterior edge of the MPR from the
maxillary to the mandibular cast

MASTICATORY MUSCLE EXAMINATION .
The masticatory muscle examination has two primary functions.
First, to identify any painful and / or trigger points.
Second, to identify the deficient masticatory muscle mass that often exists in
patients who have sustained trauma to this area or who have undergone
previous orthognathic surgery.

MANDIBULAR MOVEMENTS
Maximal interincisal opening, protrusive and excursive
movements are recorded in this evaluation.
The normal interincisal opening is about 50mm :
minimum normal protrusive and excursive movements are
approximately 6mm.
If deviations of greater than 2 to 4 mm occur during opening, they
are noted and recorded.
If opening is reduced or deviations exist, it is important to
determine if this caused by true temporomandibular joint
abnormalities or masticatory muscle problems

TMJ EXAMINATION
TMJ is palpated, auscultated and examined for any pain, clicking sounds and
for normal position and movements of condyle.

CEPHALOMETRIC EVALUATION
Most of the PA cephalometric analysis are quantitative and they
evaluate the craniofacial skeleton by means of linear absolute
measurements of
a.width or height,
b.Angles,
c.Ratios and
d.Volumetric comparison.

RICKETTS ANALYSIS
Construction of midsagittal plane.
A transverse plane is constructed by connecting the center of the
zygomatic arches, then a perpendicular is constructred to the transverse
plane through the top of the nasal septum or crista galli.
Skeletal asymmetry is evaluated
by relating the point ANS and
pogonion to this mid sagittal plane.
Denture Assymetry can be evaluated
by relating the upper and lower incisor
roots to the midsagittal plane.

Using the MSR plane Various transverse and vertical reference
planes are constructed to measure the
Nasal cavity width,
Mandibular width,
Maxillary width,
Intermolar and intercuspid width which are then compared with
the clinical norms of Ricketts.
SVANHOLT AND SOLOW -
This method aims to analyse one aspect of transverse cranio-facial
development, namely the relationship between the midlines of the
jaws and the dental arches

GRUMMONS ANALYSIS
:This a comparative and quantitative PA analysis. The analysis
consist of different components including
1.A midsagittal reference line.
2. Horizontal reference line,
3. Mandibular morphology analysis
4 Volumetric analysis.
5. Maxillo mandibular comparison
6. of asymmetry.
6. Linear asymmetry assessment.
7. Maxillomandibular relation.
8. Frontal vertical proportion analysis

The midsagittal reference line is Constructed from crista galli through
ANS to the chin point. If anatomical variations in the upper and
middle facial regions exists then the MSR plane is constructed from
the midpoint of the z plane through ANS is used as a reference
midsagittal plane .
Horizontal reference lines are
1.Z line,
2.ZA line,
3.J line.
4.One parallel to the z plane
through menton

. Mandibular morphology analysis
Triangle are formed by connecting
the head of the condyle,the antegonial
notch and the menton and the triangles
on either sideis are compared .
Volumetric analysis
polygon is formed by connecting
Condylon, antegonial notch, menton
and a perpendicular from MSR and
the right and left side polygon are
compared.

Maxillo mandibular comparison of asymmetry
Four lines are constructed perpendicular
to MSR from Ag and from J bilaterally.
Line connecting cg and J and lines from
Cg to Ag are also drawn.
Two pairs of triangles are formed in this
way,and esch pair is bisected by MSR.
If symmetry present, the constructed
lines also form two triangles namely
J – Cg – J and Ag – Cg – Ag.

. Linear asymmetry assesement
Perpendicular projection are drawn from
the MSR to CO, NC, J, Ag and Me and
the linear distance from MSR to the
particular point on either side and
vertical discrepancies are calculated
Frontal vertical proportion analysis
Ratios of skeletal and dental measurements
are made with respect to MSR and those
ratios can be compared with common facial
esthetic ratios and measurements

GRAYSON ANALYSIS
Landmarks are identified a different
frontal planes at selected depth of the
craniofacial complex and subsequent
skeletal midlines are constructed. In
this way the analysis enables
visualization of midlines and midpoints
in the third (sagittal) dimension..

HEWIT ANALYSIS
Analysis of craniofacial asmmetry
is performed by dividing the
craniofacial complex into constructed
so called traingulation of face.
The different angles, triangles and
component areas can be compared for
both the left and right side.

PANORAMIC OR FULL-MOUTH PERIAPICAL
RADIOGRAPHIC EVALUATIONS
A panoramic radiographic is evaluated for overt sinus,
intranasal(septum and Turbinates), bony, TMJ, periapical,
periodontal and dental pathology

ADJUNCTIVE EVALUATIONS A number of patients seeking consultation for
correction of their facial deformity benefit from additional evaluation to ascertain more
completely the true nature of their deformity or to plan better for treatment. The
following is a list of adjunctive evaluations that have been psychologic evaluation
A. Comprehensive psychologic evaluation
B. Computer-assisted analysis 1 Video manipulation 2.Three-dimensional
3. CT scan reconstruction
C.Additional radiographs1.Rest-position lateral cephalogram 2.Temporomandibular
joint laminograms 3.Sinus series 4 Computed tomographic scans
5.Radionucleotide scans
D.Diagnostic occlusal splint
E Nasoendoscopy
H Masticatory muscle evaluation
1.Electromyography and bite force determinations
2.Masseter muscle biopsy.

TREATMENT PLANNING
A.MAKING THE BASIC SURGICAL DECISIONS,
B.MAKING THE BASIC ORTHODONTIC DECISIONS, and
C.DETERMINING THE SEQUENCE OF ORTHODONTICS AND SURGERY TO
ARRIVE AT THE FINAL TREATMENT PLAN. .
A,MAKING THE BASIC SURGICAL DECISION The basic decision is based on
the list of esthetic treatment objectives determined from the patient's chief
complaint and the facial esthetic examination. This information is used to
create a list of orthognathic surgical procedures that would improve the
patient's facial appearance.The surgical procedures depends up on
A.Anteroposterior position of the jaws
B.Exposure of the upper anterior teeth
C.Cant of the occlusal plane relative to the lips
D.Dental midlines relative to the facial midline
E.Mediolateral symmetry of the posterior dental arches relative to the sagittal
plane

MAKING THE BASIC ORTHODONTIC DECISIONS Once the surgical
procedure (s) has been decided upon, the basic orthodontic
decisions must be made. These decision are predicated on the
surgical procedure to be done and cannot be made before
deciding on the surgical procedure (s). The orthodontic decisions
that must be made are
1.What tooth movement is necessary?
2.What are the anchorage requirements for this movement?
3. Do teeth need to be extracted?
4.If so, which teeth are to be extracted?
5.Are there tooth mass problems?, and
6 Is there sufficient alveolar bone?

THE SEQUENCE OF ORTHODONTICS AND SURGERY
As a General principle, it is preferable to perform the
orthognathic surgery as early in the patient's treatment as possible
for the following reasons.
I.Orthodontic tooth movements is more rapid for about 3 months
following surgery because the rate of bone remodeling is
increased as the result of surgery; And
2.The patients facial appearance is improved earlier in treatment,
thus improving both self-image and patient cooperation.

THE "TWO-PATIENT" CONCEPT was developed to deliberately
determine the sequence of orthodontic and surgery. This involves
1.Performing feasibility model surgery consistent with the
planned surgical procedure regardless of the occulsion so
produced, before any orthodontic treatment and
2.Making a cephalometric prediction tracing illustrating the effect
of surgery prior to any orthodontic tooth movement. Once the
feasibility model surgery and prediction tracing are done,these
records are viewed as a "second patient" one who manifests the
results of the indicated orthognathic surgery prior to any active
orthodontic treatment. The orthodontist can then decide if it
would be easier to treat the patient after the surgery or if it would
be preferable to resolve specific orthodontic problems before
surgery.

THE SEQUENCE OF TREATMENT MAY BE
SURGICAL PHASE PRE. SUR ORTHO
ORTHODONTIC PHASE SURGICAL PHASE
POST. SUR. ORTHO

ASYMMETRIC CLASS II DENTOFACIAL DEFORMITIES
ETIOLOGY
11.Congenital or acquired condylar ankylosis
2.Acquired secondary to a displaced subcondylar
3.Class II dentofacial deformities in hemifacial micros
The usual orthodontic – surgical approach it concludes
1. Presurgical orthodontic treatmen
2. Immediate presurgical planning
3. Orthognathic reconstrictive surgery
4. Post surgical orthodontic treatment

PRESURGICAL ORTHODONTIC TREATMENT
The presurgical orthodontic treatment for the asymmetric
patient is generally more difficult than that for symmetric
dentofacial deformities.
Unlike the symmetric anteroposterior deformities in which the
presurgical orthodontic treatment ultimately affects primarily
the profile esthetics, the presurgical orthodontic treatment also
has a profound influence on the front face esthetics in the
asymmetric dentofacial deformities

1.APPROPRIATE EXTRACTIONS WHEN INDICATED
symmetric extractions are usually indicated when the
transverse dental compensation are minimal with generalized
crowding and/or AP dental compensation. Asymmetric
extractions are usually where there is extreme dental
compensation.
2.Upright posterior teeth as necessary to remove transverse
dental compensation.
3.Leveling and aligning 4. Closure of residual
5.Extractions spaces
6.Elastics a.To complete removal of dental compensation
b.To correct maxillary dental midline to the facial midline
c.to correct mandibular midline to the mandibular skeletal
midline

IMMEDIATE PRESURGICAL PLANNING
1.Prediction tracing
2.Model surgery
3.Split construction.
The purpose of prediction training is to plan the details of the
surgical movement, the method of fixation (rigid, semi rigid,
skeletal suspension), the intraosseous wire or screw positions,
the necessity and magnitude of adjunctive procedures, such as
genioplasty, and / or cosmetic augmentation procedures
Asymmetric predictions are generally less accurate than
symmetric prediction because part of the movement is in the
third dimension, which cannot be well-illustrated. However,
these predictions serve as a guide for extractions, anchorage,
and the desired presurgical orthodontic tooth movement

ASYMMETRIC CLASS II DENTOFACIAL DEFORMITY CAUSED BY
CONDYLAR ANKYLOSIS.
IN GROWING PATIENT.
a.only condylar ankylosis condylar ankylosis with co existing
class II asymmetric dentofacial deformity
Effective surgical release of the ankylosis
with the resumption of good jaw movement
and masticatory function is the primary
objective of treatment
1.Release of condylar ankylosis and
subsequent correction to the
dentofacial deformity
2.performing both release of the
ankylosis and correction of skeletal
deformity simultaneously.

The surgical procedure is performed in the following
sequence
1.surgical release of the mandibular condylar ankylosis by a
retro-submandibular approach
2.mobilization, advancement, and skeletal stabilization of the
affected side of the mandible such that the skeletal midline of
the mandible is made compatible with the facial midline
3.obtainment of the autogenous costochondral rib graft
4.insertion of the constochondral graft

IN NON GROWING PATIENT
The surgical procedure to simultaneously release the
ankylosis and to correct the existing asymmetric Class II
dentofacial deformity is done in the following sequence :
1.perform the transfacial, retromandibular release of the
condylar ankylosis
2.perform the indicated genioplasty ;
3.obtain the costochondral graft while
4.the contralateral sagittal ramus osteotomy is simultaneously
performed;
5.place skeletal intermaxillary fixation

ASYMMETRIC CLASS III DENTOFACIAL DEFORMIES
Here the asymmetric Class III dentofacial deformity specifically used to
identify those dentofacial deformities that are manifest primarily as
anteriorposterior asymmetric Class III dentofacial
deformities. The primary deformity in the
asymmetric Class IIIindividual generally
exists in the mandible.
Etiology- unknown They can be caused by
1.Isolated unilateral excessive
anteroposterior mandibular growth.
2.unilateral deficiency of anteroposterior
maxillary growth, or
3.Any combination of these two conditions
that will result in an asymmetric Class II
occlusal or skeletal relation

Orthognathic reconstructive surgery
1. Modified Class III sagittal ramus osteotomies
2.Optimal genioplasty
(straightening - leveling – reduction
or advancement

HEMIFACIAL MICROSOMIA
Hemifacial microsomia, or craniofacial microsomia as may be
the currently preferred terminolog, is one of the most common
head and neck syndromes. The published occurrence rate
ranges from 1 in 3500 to 1 in 5000 live births, with a 3:2 male
predominance
The malformation complex includes
Variable of the orbit,ear mandible,
facial soft tissues and seventh cranial
nerve.
..

Pruzansky divided the mandibular component of hemifacial
microsomia into three types based on the anatomy of the
mandible and the temporomandibular joint (TMJ). In Type I-
The TMJ and ramus are of normal architecture but
are anatomically small
Type II skeletal deformities present with a hypoplastic TMJ,
ramus, and glenoid fossa on the affected side.
A- Presents with a malformed TMJ apparatus,which is positioned so
that it allows symmetric opening of the mandible with a definitive
Possterior stop
B- has a hypoplastic TMJ apparatus, but is grossly malformed so that
the definite posterior stop is absent and the patient cannot function
adequately

Type III is the most severe form or hemifacial microsomia in
which the TMJ apparatus is entirely absent. In some instances the
entire ramus and even some of the mandibular body may be
absent.
Most of the patients are best treated prior to completion of
growth.Even with excellent treatment with growth,most patients
will benefit from additional orthodontic treatment.
Clinically, Type I and II are similar in their presentation and
treatment, while the of both Type II B and III involves
reconstruction of TMJ to variable degree.

Treatment during active facial growth
Two options are considered
1.Orthodontic functional appliances may be used to attempt to
stimulate growth on the affected side, thus producing more
equal growth during the period of active facial growth with
subsequent surgery
2. Early surgery to improve facial appearance and facial
growth, thereby reducing the severity of the adult deformity,
followed by orthodontic treatment.

ORTHOPEDIC PHASE The orthopedic phase treatment
involves the use of a series of appliances that progressively place
the mandible vertically and transversely into a more "normal"
position. Doing so has positive effects on the facial appearance
and the neuromuscular function. It also produces a "stretching" of
the deficient soft tissues (i.e normalizing the functional matrix) in
preparation for the subsequent surgery. It does not produce more
normal mandibular growth and requires excellent patient
compliance.

HYBRID FUNCTIONAL APPLIANCE
In asymmetric patients,symmetric advancement of the mandible with
conventional myofunctional appliance(like activator,bionator)is not
possible,so a appliance should be made to achieve desired asymmetric
jaw movements and dento alveolar changes
Hybrid appliance is made up of a
set of appliance compnents
in a unique way that effect
dentoalveolar and skeletal changes
by manipulating the processes of
eruption, growth, and adaptation

The available literature shows that the response to functional
orthodontic appliances are unpredictable in this patient
population.
In general, the less severe the three-dimensional nature of the
existing dentofacial deformity and the more normal the existing
mandibular movements, the more likely a given patient is to
have a positive response to functional appliances.
Indeed, functional appliances have not been shown to produce
clinically relevant improvement of facial growth in patients
with hemifacial microsomia
SURGICAL OPTION
surgical lengthening of the mandible on the affected side by
either distraction osteogenesis or rotational advancement of the
mandile with or with out autogenous bone graft followed by
orthodontic treatment

FACTORS TO BE CONSIDERED BEFORE ORTHOPAEDIC
PHASE
1.the age of the patient
2.the severity of the existing dentofacial deformity and
3.the measured response to the orthopedics once a decision has
been made to use them.
This is done to improve the facial appearance, stretch the deficient
soft tissues, level the maxillary occlusal plane, and stimulate
neuromuscular function. It does not effect more normal growth of
the mandible or eliminate the need for future surgical
intervention.

TREATMENT AFTER COMPLETION OF ACTIVE GROWTH
Mild to moderate dentofacial deformity
1.Modified sagittal osteotomies
with optional advancement geniplasty
and /or
2.unilateral mandibular augmentation
using alloplastic graft material
.

Moderate to severe dentofacial deformity
1.Simultaneous mandibular ramus and maxillary surgery with
secondary advancement genioplasty and/or
2.unilateral mandibular augmentation.
The decision to perform simultaneous
mandibular and maxillary surgery is
predicated primarily on the existence
of a clinically significant cant of the
maxillary occlusal (maxillary teeth)
relative to the upper lip at rest and
during smiling

SEVERE DENTOFACIAL DEFORMITY
ORTHOGNATHIC RECONSTRUCTIVE SURGERY
The first stage is combined simultaneous repositioning of the
maxilla and mandible.It includes
1.Le fort I maxillary osteotomy
2.Ramus osteotomies with or without bone grafting and
preservation of the existing articulation (condyle)
3.Autogenous reconstruction of the TMJ articular anatomy, and
4.Alloplastic reconstruction of the TMJ articular anatomy
The second stage includes the indicated genioplasty,
augmentation of the mandibular, frontal, and malar-orbital
areas, and reconstruction of the soft-tissues.

SEVERE DF DEFORMITY WITH EXTENSIVE AGENESIS OF
THE MANDIBLE.
COMPOSITE AUTOGENOUS RIB AND CACELLOUS ILIUM RECONSTRUCTION
MICROVASCULAR GRION FLAP The cartilage containing portion of the rib
graft is contoured to resemble the normal mandibular, and the rib is
sectioned and fashioned to simulate the
inferior and superior border of mandible
The two rib cortices act as a matrix for the
new mandible. The large defect between
them is filled with autogenous cancellous
bone obtained froma single posterior iliac
crest or from both anterior iliac crestwww.indiandentalacademy.com

In severe cases addition of bone to the deficient mandible may not
provide sufficient stretch of the overlying soft tissue to allow a
symmetric relation of lips with facial midline.
In these patients
•Microvascular grion flap or
•Avascularised osteocutaneous grion flap is used

UNILATERAL HYPERPLASTIC CONDITION OF THE CONDYLE
Unilateral hyperplastic conditions of the madibular condyle result primarily
in vertical deformities of the facial skeleton with variable degrees of
1.unilateral elongation of the mandibular
condyle/ramus
2.unilateral posterior open bite
3unilateral bowing of the inferior border
of the mandible
4.different mandibular dental midline
than facial midline and / or
5. compensatory cants of the maxillary
occlusal planes. Midsymphysis deviated
to the opposite of the affected condyle

The treatment depends up on
1.whether the condyle is actively growing or not
2. The nature of growth ie whether the growth is hyperplastic or
osteochondromatous in nature.
Technetium 99 is used to differentiate whether the condyle is actively
growing or not, by comparing the difference in up take of T 99 by the
hyperplastic and the normal condyle

HYPERPLASTIC CONDYLE OSTEOCHONDROMA
1.The condyle is normal in shape with condyle is irregularly enlarged
an obviously elongated neck
2.Grows more rapidly grows slowly
3.It is self limiting pathologic process continue to grow slowly
until it is surgically removed
4.usually asymptomic mandibular dysfunction
and/or pain may coexist

TREATMENT OF ACTIVE UNILATERAL HYPERPLASTIC CONDYLAR
GROWTH
In case of Early diagnosis and no co existing DF deformity
There is minimal changes in the mandible,maxilla and occlusion
High condylectomy
In case late diagnosis with severe DF deformity or unilateral
hyperplastic condition with co-existing DF deformity
High condylectomy + the indicated orthognathic and reconstructive
surgery

IN CASE OF OSTEOCHONDROMA ASSOCIATED WITH DF DEFORMITY
Condylectomy and reconstruction with an autogenous costochondral rib
graft
TREATMENT OF ARRESTED UNILATERAL HYPERPLASTIC GROWTH
There is no need to perform a high condylectomy. Rather, the
correction of the dentofacial deformity secondary to arrested
condylar hyperplasia consists of appropriate presurgical and
postsurgical orthodontic treatment in concert with the indicated
mandibular and/or maxillary surgery.

TREATMENT OF CROSS BITE
factors to be considered
1Age and growth potential of the individual
2.Type of cross bite- dental or skeletal
3.Anterior or posterior
APPLIANCES USED
REMOVEABLE APPLIANCE-includes catlans appliance posterior bite plane with Z spring
BANDED APPLIANCE -lingual arch, quard helix
MYOFUNCTIONAL APPLIANCE face mask for maxillary retrusion reverese activator, FR III
and chin cap for excessive mandibular growth
EXPANSION SDREWS- slow and rapid palatal expansion screws
FIXED APPLIANCE-asymmectrically expanded arch wire and cross elastics
OCCLUSAL GRINDING- if the asymmetry is due to any occlusal interferences

CONCLUSSION

Facial asymmetry

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Facial asymmetry