Ayoubs lectures Flashcards
What classifications of maxillofacial fractures are there
- Baso ethmoidal
- Lateral middle third (zygoma)
- Central middle third
- Mandibular fractures
What is meant by a lateral fracture
Fracture of the zygoma
In orbital and naso-ethmoidal injuries what must you consider
The 4 walls, an anterior surface and apex:
-Anterior wall
-Medial wall
-Floor
-Lateral wall
-Roof
-Apex
What does the anterior of the NOE have
eyelids
cornea
sclera
What does the medial wall of the NOE are have
medial rectus muscle
nose
lacrimal duct and sac
medial canthal ligament
ethmoid sinus
cribriform plate
What does te superior orbital fissure contain
Occulomtor nerve III
Trochlear nerve IV
Abducent nerve VI
branches of ophthalmic nerve
ophthalmic veins
What does the inferior orbital fissure contain
Infraorbial nerve, vein and artery
What would a symptom of a maxilla sinus fracture be
Bleeding nose through the semilunar hiatus
What is a malar fracture
A fracture that primarily involves the suture lines of the zygomatic bone
What are symptoms of a zygomatic fracture
Flat face
Double vision
Restricted eye movement
Numbness to face
Limited jaw movement
Wha are clinical signs of a malar fracture
Periorbital bruising & swelling
Subconjunctival ecchymoses
Sensory deficit -Infraorbital nerve
Diplopia / Visual impairment
Subcutaneous emphysema
Epistaxis
Step deformit
What is a sign of a sub-conjunctival haemorrhage
Circumorbital ecchymosis
Why could there be a limitation of jaw movement in a zygoma fracture
The fracture impinges of te coronoid process
Wha would the eye look like in a orbital fracture
Would appear sunken in
What is an open reduction
the broken bone is realigned during surgery
What is a closed reduction
a procedure to set (reduce) a broken bone without cutting the skin open
The broken bone is put back in place, which allows it to grow back together in better alignment
What is the gilles approach
Most common way to reduce a fracture and it is a closed reduction
Involves a temporal hairline incision placing an elevator superficial to the surface of the temporalis muscle under the deep temporal fascia and sliding the elevator under the arch to lift it into reduction
What TMJ diseases are there
TMJ dysfunction
Jaw dislocation
Osteo-arthritis
Rheumatoid arthritis
Chondromatosis
Foreign body granuloma
Infection
Traumatic damage
Radiation damage
Ankylosis
Tumours
What is the aetiology of TMD
Macrotrauma
Microtrauma – chronic joint overloading
secondary to stress related repetitive
clenching or Bruxism
Occlusal factors
a) deep bite
b) occlusal disharmony
c) lack of teeth
Anatomical factors- Class II jaw relation
What does the articulator cartilage consist of
Chondrocyts
Collagen fibres in proteoglycan
matrix
Wha tcould cause TMJ pain
Compressive forces – may damage proteoglycans which protects collagen
Inflammation produces proteases & hyaluronidase
Synovitis > chronic adhesive capsulitis & disc
displacement
Shearing forces may then cause break up of
collagen fibrils
What are the functions of a bite appliance
Eliminates occlusal interferences
Prevents the joint head from rotating so
far posteriorly in the glenoid fossa
Reduces loading on the TMJ
What investigations of the TMJ asre there
Arthrogram
MRI scan
Arthoscopy
What can you carry out in arthoscopic procedures
Diagnosis
Biopsy
Lysis and lavage
Disc reduction – release, cautery, suturing
Removal of loose bodies
Eminectomy
What is the bilaminer zone and whats in it
located between the posterior band of the TMJ disc and the posterior portion of the TMJ capsule
It has collagen fibres that allow anterior translation of the disc over the articular eminence and also help to maintain relationship with the mandibular condyle
What surgical procedures are there that involve the TMD and ramus
Disc plication
Eminectomy
High condylar shave
Condylotomy
Meniscectomy
Condylectomy
What is a disc plication
When the TMJ disc is repositioned
Could involve removing segment of bilamner zone
What is an eminectomy
A surgical procedure that reduces the articular eminence to correct chronic dislocation or closed lock of the mandible
What is a condylotomy
surgery in which the mandibular condyle is partially or completely removed
What are the indications for TMJ reconstruction
Joint destruction:
(a) Trauma
(b) Infection
(c) Tumours
(d) Previous surgery
(e) Radiation
Ankylosis
Developmental deformity
Tumours – usually
slow growing
(i) Giant cell lesions
(ii) Fibro-osseous
lesions
(iii) Myxomas
What are the ankylosis classifications of TMJ
Type I – Flattening deformity of condyle, little
joint space & extensive fibrous adhesions
TypeII – Bony fusion at outer edge of articular surface
TypeIII – Marked fusion bone between upper part of ramus of mandible & zygomatic arch
TypeIV – Entire joint replaced by mass of
bone
