TMD Surgery

Question 1

Aetiology of TMJ dysfunction

Answer 1

• macrotrauma - hit in joint damage
• microtrauma - chronic joint overloading secondary to stress related repetitive clenching or bruxism
• occlusal factors
  
  • deep bite
  • occlusal disharmony
  • lack of teeth
• anatomical factors - class III jaw relation

Question 2

TMJ anatomical landmarks

Answer 2

• glenoid fossa
• condylar head
• articular disc
• lateral ligament
• inner surface of capsule
• synovial membrane

Question 3

How is disc moved forward and back

Answer 3

• disc follows movement of condyle , swings in synovial fluid
• disc attached anteriorly by ligament of lat pterygoid muscle - brings forward
• counteract movement by posterior bilaminar zone , collagen bundle brings disc back
• fluid secreted by synovial membrane

Question 4

What does articular cartilage consist of

Answer 4

• chondrocyts
• collagen fibres in proteoglycan matrix

inflammatory disease produces proteases which degrade proteoglycans

Question 5

Surgical procedures for TMJ

Answer 5

• disc plication
• eminectomy
• high condylar shave
• condylotomy
• menisectomy
• condylectomy
• reconstructive procedures

Question 6

Ankylosis classification

Answer 6

• type I - flattening deformity of condyle, little joint space and extensive fibrous adhesions
• type II - bony fusion at outer edge of articular surface
• type III - marked fusion bone between upper part of ramus of mandible and zygomatic arch
• type IV - entire joint replaced by mass of bone