Temporomandibular Joint Flashcards
What type of synovial joint is the TMJ
Ellipsoid jt
What are the 4 types of movements
Anteroposterior gliding
rotation around horizontal axis
lateral deviation
circumduction
What part of the jt capsule is lax
between disc and temporal bone– allows for variety of movements
What part of the jt capsule is Tight
Between the disc and the condyle of mandible– ensures that the disc fits tightly to head of mandible
How many jt spaces are in the TMJ
2– superior and inferior
Which jt space has the most movement and why
the superior jt space, because its the most extensive
What are the two accessory ligaments for the TMJ
stylomandibular ligaments
sphenomandibular ligaments
Do either of the accessory ligaments actually connect to the TMJ
No
What nerves innervate the TMJ
auriculotemporal nerve –>branch of V3 –>branch of trigeminal
What happens during phase 1 of opening of the mouth
Disc and condyle slide anteriorly against mandibular fossa
Results in slight protraction and depression of mandible
Associated with motion of superior jt space
What occurs during phase 2 of opening the mouth
Hinge like rotation of the condylar process of the mandible against the articular disc
Associated with the motion of the inferior joint space
What does the motion of phase 2 result in
complete depression of the mandible
When is the TMJ most prone to dislocation, and which direction does it usually dislocate
When mandible is fully depressed
Displaced anterior articular tubercle
Where is pain from the TMJ usually referred to
Temporal region and external ear
