TMJ Flashcards
What type of joint is the TMJ?
synovial
What movements occur at the head of the mandible?
- AP gliding
- rotation
- lateral deviation
What bony elements make up the TMJ?
- condyloid process of the mandible
- mandibular fossa of the temporal bone
- articular tubercle of the temporal bone
What type of tissue makes the TMJ articular disc?
denses fibrous CT
Where does the articular disc of the TMJ anchor and how does it fit within the joint?
it anchors peripherally to the joint capsule such that it is taut against the condyloid process for stability and rotation and creates a lax space between it and the mandibular fossa for AP gliding and lateral deviation
What are the ligamentous structures of the TMJ?
- joint capsule
- stylomandibular ligament
- sphenomandibular ligament
What is the span of the stylomandibular ligament?
apex of the styloid process to the angle of the mandible
What is the span of the sphenomandibular ligament?
from the spine of the sphenoid to the medial surface fo the mandible near the mandibular foramen
Depression of the mandible is initiated by what?
a small degree of rotation of the condyloid process
Following initiation of depression of the mandible, what 2 steps occur in the TMJ to open the mouth further?
Step 1: disc and condyle glide anteriorly against the mandibular fossa and onto articular tubercle - associated with motion of the superior joint space
Step 2: hinge-like rotation of the condyloid process of the mandible against the articular disc - associated with motion of the inferior joint space
What primarily provides sensory innervation to the TMJ?
auriculotemporal nerve (from V3)
What is the function of the stylomandibular ligament
and sphenomandibular ligament
suspend the mandible from the skull - neither directly connect to TMJ
