for orthodontist

1. Hemifacial Microsomia
Terminology
 First and second brachial arch syndrome
 First and second branchial arch deformity or syndrome
 Oculoauriculovertebral dysplasia
 Oculoauriculovertebral spectrum
 Otomandibular dysplasia
 Otomandibular dysostosis
 Lateral facial dysplasia
 Unilateral craniofacial microsomia
 Unilateral mandibulofacial dysostosis
Introduction
 Congenital asymmetry of the lower face
 Hemifacial macrosomia is the most frequently encountered form of isolated facial
asymmetry.
 The findings can be viewed as similar to those of TCS, but mainly these findings are
unilateral, causing gross facial asymmetry.
 It could be bilateral in 16%
 Affects 1st and 2nd branchial arch structures
 Goldenhars (oculoauriculovertebral dysplasia) thought to
be variant of hemifacial microsomia, with eye tumors and fused
spines in addition to the characteristic facial asymmetry thus
collectively called: Oculo-auriculo-vertebral spectrum
(OAVS).
 Better description is Craniofacial microsmia because
it accounts for cranium involvement and 30% bilateral (Gill
2015)

2. Etiology
1. Sporadic:
 Tetragon (Thalidomide, retinoic acid)
2. Stapedial artery hematomas at approximately 30–45 days of gestation. At approximately
the 32nd day of intrauterine life the normal process of atrophy of the stapedial artery occurs,
allowing the switch of the blood supply to the face from the internal carotid to the external
carotid artery
3. Familial: 2-10% familial/genetic (Gene mapping has indicated a link to a region on
chromosome 10).
 Incidence
 1; 5,600
 M: F 3:2
 Bilateral in 10%
 R: L 3:2
 CLP 15% (CP twice as likely)
Feature
1. Ocular
 Anophthalmia or microphthalmia may also occur.
 Colobomata or Coloboma of the iris or eyelids
with the absence of the eyelashes is a frequent finding.
 Ptosis of the upper eyelid (dropping of the upper
eyelid as a result of levator palpebral muscle function)
with narrowing of the vertical palpebral fissure is often seen.
 Deficiencies of the lateral canthi with a decreased horizontal fissure are
common.
2. Ear

3.  Hearing loss may result from underdevelopment of the osseous components of
the auditory system and a diminished or absent external auditory meatus.
 Anotia to a mildly dysmorphic ear or unilateral microtia
 Pre-auricular skin tags: between tragus and corner of mouth (area of fusion of
Maxillary Mandibular processes). The skin tags of HFM represent epithelial remnants
of the fusion of the maxillary and mandibular processes of the first branchial arch.
3. CN involvement: Facial nerve palsy (25-40%)
 1st BA n = trigeminal usually okay
 2nd BA n – facial n. lower braches affected
 Severity of facial nerve involvement does not relate to degree of skeletal
involvement
4. Facial features:
 Facial asymmetry
 Dystopia
 Orbital hypoplasia
 Malar hypoplasia
 Maxillary hypoplasia
 Mandibular hypoplasia
 Agenesis of the ramus
 Hypoplastic glenoid fossa
 Hypoplastic condyle
 Hypoplastic coronoid process
 Hypoplastic ramus
 Hypoplasia or absence of muscle of mastication. According to the research of
Kane and colleagues, in patients with HFM, the extent of hypoplasia of specific muscles
of mastication frequently predicts the extent of dysplasia of the osseous origin and

4. insertion of those muscles. If the temporalis muscle is hypoplastic, a deficiency of the
coronoid process will be present. When the masseter muscle is hypoplastic, the gonial
region of the mandible will also be deficient. When the lateral pterygoid muscle is
deficient, the condylar head is deficient or absent. For any degree of muscle
hypoplasia there is a similar degree of skeletaldysmorphology. The opposite is not
true.
 Microgenia
 Macrosomia due to failed fusion of Mx and Mn process
5. Intraoral features
 Delayed teeth eruption,
 Hypodontia and Hypoplastic teeth (25%): Dentin is of neural crest origin. It
generally is accepted that normal odontogenesis requires the presence and interaction
of neural crest ectoderm and mesenchymal cells. Disturbances in the odontogenic
process can produce abnormal or incomplete dental development. Maruko and
colleagues postulated that the increased incidence of hypodontia documented in
patients who have HFM may be attributed to a disturbance in neural crest cell
development.
 Cross Bite
 Lateral and anterior Open Bite
 Midline asymmetry
 Occlusal plane canting with ipsilateral shortening (Padwa 1997). The results
of this study indicate that 4 degrees is the threshold for recognition of an occlusal cant
by 90% of people)
 CLP or CL 25%
 Velopharyngeal insufficiency - ? DiGeorge Syndrome
6. Airway problem
7. Cardiac problem 50%
8. Renal or genitourinary anomalies problems

5. Differential diagnosis:
 VACTERL is an acronym for
Vertebral anomalies, Anal atresia, Cardiac
malformations, Trachea, Esophageal fistula,
Renal Anomalies, and Limb anomalies.
 Nager syndrome: downward
palpebral fissures, midface hypoplasia, micrognathia, and upper limb (radial)
deformities. Features are usually bilateral.
 TCS: bilateral midface and mandibular hypoplasia, microtia, and coloboma.
Diagnosis
 Family history
 Clinical examination
 OPG
 Ceph
 AP adiograph
 CBCT
 CT
 MRI
 Photo
 3D photo
 Laser
 Genetic analysis
Classification of Hemifacial Microsomia
Mn classification originated from Purzansky 1969 and Kaban 1991, then OMENS added the
Mn to it – Vento & Le Brie 1991
Mandible modification by Kaban (Purzansky 1969, Kaban 1981 & 1991)

6. I – small condyle, under developed muscle of mastication (MoM)
IIa – hypoplastic condyle, hypoplastic MoM, absent/hypoplastic glenoid fossa
IIb – rudimentary condyle, rudimentary/absent MoM, glenoid fossa absent
III – condyle/glenoid fossa absent, rudimentary/absent MoM
OMENS Classification (Vento & LeBrie 1991)
The mandible is same as Purzansky
O – Orbital asymmetry
M – Mandibular hypoplasia
E – Ear anomalies
N – Nerve involvement
S – Soft tissue involvement

7. The number are added together Therefore, 15 would be the maximum score
possible
Management:
Initial assessment
New born child:
1. Pediatrician: kidney, heart, Airway – trachy? OSA
2. Ophthalmology: 15% ophthalmic protection due to facial paralysis
3. CP
4. Feeding
5. Audiology: hearing loss 15%
6. Speech

8. Early intervention (>3 years)
1. Cleft
2. Macrostomia
3. Skin tags
4. Facial n innervation
5. Occluar protection
6. Hearing (BAHA)
Mixed dentition:
 Airway: OSA
 Ocular protection
 Safe and effective first-stage Le Fort I osteotomies carried out during the mixed
dentition are not practical as a result of the location of the developing teeth and the expected
inhibition of any postoperative horizontal maxillary growth.
 Hybrid functional appliance alone
 Ramus reconstruction alone
 Hybrid functional appliance and ramus reconstruction combination
I. One way of treatment distraction osteogenesis (DO) for type I, IIA
For DO to be effective, a functional glenoid fossa and an adequate condyle must be present
(i.e., in the presence of Type I or Type IIA malformation).
It is a method of increasing bone length & originally described by Ilizarov (1988). The
technique involves:
1. Corticotomy – circumferential sectioning of compact bone and maintenance of
medullary complex.
2. Screw device holding bone pins rigidly and then the two pieces are separated in
a controlled and gradual process, which induces bony proliferation between them.
3. Screw turned after 5 days
 1mm/day – adults
 2mm/day – children
 Insufficient speed = bony union
 Undue haste = fibrous non-union

9.  Traction forces applied to bone also create tension in the soft tissue, initiating a
sequence of adaptive changes termed distraction histogenesis.
Interestingly, most published reports of first-stage mandibular reconstruction in
patients with HFM do not fully justify it (Meazzini et al 2012). Those authors conducted
a comparison study of long-term follow up until the completion of facial growth of two
homogenous samples of children with HFM. The experimental group was treated with
mandibular DO during the deciduous or early mixed dentition in an attempt to correct
the mandibular deformity. The control group was not subjected to any treatment until
adulthood. The experimental group included children (n = 14) who underwent
mandibular ramus osteotomies with DO (mean age, 5.9 years) with a mean follow up
of 11.2 years. With the use of quantitative measurements on serial panorex radiographs,
the DO group was compared with the control group (n = 8). The study results document
that facial proportions in patients with HFM are maintained throughout growth when
no treatment is undertaken. Unfortunately, after ramus osteotomies with DO, the
mandibular disproportions returned to their original level of asymmetry during growth.
The authors concluded the following: 1) HFM does not progress with regard to the
degree of facial asymmetry or deformity when the patient is left to mature naturally and
2) early intervention with mandibular ramus osteotomies and DO does not effectively
reduce long-term facial asymmetry in the patient with HFM. In published reports, most
children with HFM were still rated as “unattractive” after surgery and showed no
“improvement in self-esteem.” Children with HFM have an elevated risk for childhood
psychosocial difficulties. The only indication is if there is an airway issues.
II. Second way of treatment for type IIB, III involves an autogenous replacements for
the condyle and a hybrid functional appliance in different phases.
Way for autogenous replacements for the condyle have included:
the metatarsal bones

10. the proximal head of the fibula
the costochondral junction of the rib (CCJ/rib) (6th or 7th)
the sternoclavicular joint.
a. Very Early intervention at age of 5-6 years
 Functional appliance
 Then Surgery
 Then functional appliance
b. Early intervention at age of 8-9 years
 Surgery
 Then Functional appliance
Ongoing problems when choosing the costochondral graft option to be carried out during the
mixed dentition for the Type IIB or III malformation include overgrowth, undergrowth,
ankylosis, and resorption of the mandible (third of the ribs not growing, a third growing within
the normal range, the remaining third presenting with overgrowth). The overgrowth concerns
are diminished but not eliminated when the costochondral graft procedure is carried out in a
child who is in the late mixed dentition stage (i.e., 9 to 11 years old) and in whom only a
minimum amount of cartilage (i.e., ≈2 mm) is left at the articulating surface of the graft.
Permanent dentition and late reconstruction after age of 13 years
The rationale for postponing the correction of the dentofacial deformity until the time of “early”
skeletal maturity is the same as that for the correction of the jaw deformity associated with a

11. repaired cleft palate and most other routine dentofacial deformities. This rationale includes the
consideration of the following:
o avoiding injury to the developing permanent dentition and the inferior alveolar nerves
o avoiding soft-tissue scarring
o avoiding the loss of ramus marrow space that will complicate the success of necessary
redo ramus osteotomies
o minimizing negative psychosocial memories of earlier jaw surgery that may prevent the
patient and family from later pursuing definitive reconstruction and
o avoiding the iatrogenic three-dimensional deformation of the mandible that limits long-
term success.
o In addition, any orthodontics carried out during the mixed dentition will not be reflective
of the permanent dentition; a final course of braces would also be required.
1. Orthodontics
As with other dentofacial deformities, extractions may be required to orthodontically relieve
dental root crowding and to normalize the inclination of the anterior teeth in preparation for the
surgical repositioning of the jaws.
2. Surgery
 Type I and IIA mandibular malformations are best reconstructed after all of the
permanent teeth have erupted and orthodontic goals have been reached. Surgical objectives can
be met by making use of sagittal split ramus osteotomies of the mandible in combination with
Le Fort I osteotomy (often in segments) and osseous genioplasty.
 For Type IIB mandibular malformations, costochondral graft reconstruction of the
deficient condyle ascending ramus at the time of skeletal maturity remains this surgeon’s
preferred approach in most cases despite its limitations. A sagittal split ramus osteotomy is
completed on the contralateral side to derotate the distal mandible. This is combined with a Le
Fort I osteotomy (often in segments) and an osseous genioplasty.
 The Type III glenoid fossa–mandibular malformation requires the surgical construction
of the congenitally glenoid fossa in addition to the mandibular reconstruction that carried out
as previously described for the Type IIB deformity.
The surgical objectives of the Le Fort I osteotomy may include the following:
1. Vertical:
 Cant correction of the maxilla

12.  Either extrusion or intrusion of the posterior maxilla on each side, depending on the
extent of counter-clockwise rotation required to achieve adequate horizontal projection of the
mandible and chin (i.e., pitch orientation)
2. Transverse:
 Correction of the maxillary dental midline to the facial
 Widening of the maxilla
3. AP:
 Horizontal advancement to improve midface projection and to open the upper airway
4. Other:
 Bone grafting of the zygomatic buttress on the ipsilateral side to improve facial
symmetry
 Provision of access for intranasal procedures (e.g., septoplasty, inferior turbinate
reduction, recontouring of the pyriform rims and the nasal floor).
3. External Auditory Canal and Middle-Ear Reconstruction
Generally, attempts to reconstruct the external auditory canal and the bones of the middle ear
for patients with HFM are not carried out as long as adequate hearing is present in the
contralateral ear
A bone-anchored hearing aid (BAHA) consists of a permanent titanium fixture that is
surgically implanted into the skull bone behind the ear and a small detachable sound processor
that clips onto the fixture. BAHAs are suitable for people with conductive or mixed hearing
loss
4. Soft Tissue Free flap:
 Antero-lateral groin or rotational from shoulder
 Coleman fat transfer (20-50% of cells lost). Adipose tissue is taken from a donor site,
thigh or abdomen (often the belly button), centrifuged intraoperatively and injected
subcutaneously into the area of deficiency. The technique has evolved with improved long term
benefit. It has the advantage of being minimally invasive. As a camouflage procedure it may be
a reasonable alternative for an adolescent until conventional orthognathic treatment can be
offered.
 External Ear Reconstruction
5. Genetic analysis

13.  Finally, those patients with known mutations will need counselling from the geneticists
as to their future plans.
At Great Ormond Street:
I, IIa
 wait until growth complete: ortho at 12 yrs,
 16-18 yrs orthognathic
IIb, III
 9yrs ramus reconstructions
 12 yrs orthodontics
 18 years: orthognathic

14. Goldenhar’s Syndrome
(Meenan 2014)
 Structures if the 1st and 2nd brachial arches affected 6th week of gestation
 Incidence- 1:26000 (Hartsfield 2007)
Etiology
 Vascular disturbances in development of NC structures of the 1st and 2nd aortic arches
 AD – APC gene mutation (part of Wnt2 pathway – expressed in initiation/ bud
formation phase)
 risk prenatal: vasodilative medication, maternal diabetes, twin pregnancies, 2nd trimester
bleeding, artificial reproductive techniques, alcohol
Diagnosis:
 Prenatal ultrasound (false –ve in 15%)
 Presence of ear tag or (triad micrognathia, glosspotisis, upper air way obstruction)
 To differentiate between GHS or Pierre Robin, look for craniofacial and vertebral
abnormalities
Clinical features;
Similar to TCS, But GHS shows
 Bilateral in 33%, both sides
maybe affected to varying degrees
 vertebral defects 24%
 epibulbular dermoids
 Microtia/atresia or ear tags
 Multiple fibromas/odontomes
 Association with colorectal cancer
 Craniofacial abnormalities: Facial n palsy (15%) with degree of asymmetry Mx, Mn
zygomatic hypoplasia

15.  TMJ abnormalities
 CLP
 Teeth: hypodontia, supernumeries, hypoplasia
Oro-maxillo-mandibular and dental intervention
Same as HFM