diseases Of TMJ by TS Flashcards
Goldenhar syndrome is a triad of what
Craniofacial microsomia, ocular dermoid cysts and vertebral anomalies. Falls under hemifacial microsomia
What are the three factors causing hemifacial microsomia
1) genetic factors - single gene mutation
2) external environmental factors - thialidomide and retinoic acid
3) intrinsic maternal factors eg gestational diabetes
What is OMENS and the meaning of it
Classification used for HFM
If OMENS score >6, increased likelihood of extracranial comorbidities
What classification used for mandible
Kabans modification of Pruzansky classification
Got type I, type II A, type II B, type III
What classification used for development of ear
Marx’s grading system (for microtia)
Grades 1-4, increasing level of deformation (ear is smaller and smaller )
What is Mx for HFM
Mandibular distraction osteogenesis +/- orthognathic surgery
Or costochondral graft + oral appliance
What is the etiology of treachercollins
- genetic disorder
- 5th and 8th week of embryonic development
- failure of neural crest cells
What are some skeletal defects for TCS
- shallow orbit
- hypoplastic zygoma
- Mandibular hypoplasia
- marked antagonism notch
- retrogenia
What is the main problem for TCS
Complex airway ( because of the retrogenia)
What are the operations to be done on patient with TCS
Mnemonic is Tr E A C H E R S
1) Tr = trachea and airway adjuncts eg tracheostomy
2) E = eye protection
3) A = Angular osteotomy and distraction of mandible in extreme retrognathia to control airway
4) C = cleft palate repair at 6 months
5) H = hearing eg bone anchored hearing aid at about 4 yo when cranial temporal bone is 4mm thick and able to hold osseointegrated implant
6) E = ear reconstruction
7) R = reconstruction of mature facial skeleton, genioplasty
8) S = soft tissue refinements eg midface lift
What are the 2 features of PRS and main associated issue?
Glossoptosis = backward positioned tongue
Micrognathia = undervelopment of jaw
Associated with airway obstruction
What is the tubingen palatal plate used for
Management of PRS, to correct the micrognathia and retrognathia
What is the definition of true ankylosis of TMJ
Fibrous or bony fusion of condyle and glenoid fossa
Causes of TMJ ankylosis
1) trauma (main aetiology )
2) infection
3) systemic diseases
3 clinical features of TMJ ankylosis
1) limitation in mouth opening
2) facial deformity
3) KIV OSA
what is the difference in clinical features for unilateral and bilateral TMJ ankylosis
1) for unilateral, there is chin pt deviation to affected side, but for bilateral it is just retrusion because both cannot grow
2) unilateral may have maxillary cant whereas bilateral is steep occlusal plane since posterior maxillary height is shortened
which deformity gives a bird face of andy gump look
bilateral tmj ankylosis
6 reasons why kids are at greater risk of TMJ ankylosis
1) articulating surfaces highly vascular
2) flat and broad glenoid fossa
3) vascular articulating disc
4) thick and stout condylar neck
5) hemarthrosis (articular bleeding into joint cavity)
6) greater osteoblastic activity
what type of facial malformations are caused by the underdevelopment of first and second pharyngeal arches
craniofacial microsomia
what muscles are derived from 1st pharyngeal arch
MOM
what nerve and artery are derived from 1st pharyngeal arch
trigeminal nerve, maxillary artery
what muscles are derived from 2nd pharyngeal arch
MOFE
what nerve and artery derived from 2nd pharyngeal arch
facial nerve, stapedial artery
what nerve and artery derived from 3rd pharyngeal arch
glossopharyngeal nerve and common carotid/ internal carotid artery
what nerve from 4th and 6th arch
vagus
what are the 3 paired prominences that fuse to form the face
1) maxillary
2) lateral nasal
3) mandibular
what is the main blood supply to TMJ
1) branches of superficial temporal
2) deep auricular
3) anterior tympanic
4) ascending pharyngeal arteries
what is the nerve supply to TMJ
from branches of mandibular division of trigeminal nerve:
1) auriculotemporal nerve
2) masseteric branch
3) deep temporal branch
what muscles help TMJ to close and open jaw
- elevate and close jaw: masseter, temporalis, medial pterygoid
- depress/open jaw: lateral pterygoid, geniohyoid, mylohyoid and digastric
what principal maxillofacial defects in hemifacial microsomia
MANDIBLE
- mandibular hypoplasia
- malformed glenoid fossa
EAR
- microtia
- preauricular tags
- conductive hearing loss
MIDFACE
- maxillary hypoplasia
- zygomatic
hypoplasia
- occlusal canting
SOFT TISSUE
- masticatory muscle hypoplasia
- cranial VII nerve palsy
diagnostic criteria for HFM
either ipsilateral mandibular and ear defects or
asymmetric mandibular or ear defects in association with either
a) two or more indirectly associated anomalies
b) positive family history of CFM
