TMJ disorders Flashcards
The joint surface of the TMJ is made up of ___.
fibrocartilage
Area of load-bearing within the TMJ is affected by what?
- congruity of contacting tooth surfaces
- head position/posture
- coordination of muscle function
Lower or upper cavity? Where spin/rotation of the condyle occurs.
lower cavity
Lower or upper cavity? Where translation/gliding of the disc and condyle along the fossa occurs.
upper cavity
What muscles are responsible for working together BILATERALLY to raise the mandible while closing the mouth?
masseter
medial pterygoid
temporalis
What muscles are responsible for working together to depress the mandible while opening the mouth?
lateral pterygoid
diagastric
Origin of the temporalis.
temporal fossa
insertion of the temporalis.
anterior border of the coronoid process
ramus of the mandile
Action of temporalis.
assists with closing the mouth
side/side grinding of teeth
stability
origin of the superficial layer of the masseter.
anterior portion of the lower order of zygomatic arch
origin of the deep layer of the masseter.
medial surface of the zygomatic arch
insertion of the masseter.
blend with the medial pterygoid and then inserts on the coronoid process, ramus, and angle of the mandible
Action of the masseter.
elevates mandible when closing the mouth bilaterally
ipsilateral lateral deviation of the mandible (when acting indiv.)
origin of medial pterygoid
medial aspect of the mandibular ramus
insertion of the medial pterygoid
posterior aspect of the angle of the mandible
action of the medial pterygoid
closes the mouth bilaterally
deviate mandible to the contralateral side individually
Origin of the superior division of the lateral pterygoid.
sphenoid
action of superior division of lateral pterygoid
assists with chewing
rotates the disc ANTERIORLY on the condyle during closing of the mouth
origin of the inferior division of the lateral pterygoid
lateral pterygoid plate
action of the inferior division of the lateral pterygoid
assists with opening the mouth
protrudes the mandible
contralateral lateral deviation
insertion of lateral pterygoid
neck of mandible condyle
capsule of TMJ
TMJ arthrokinematics of mouth opening, contralateral deviation, and PROT
mandible rolls anteriorly
glides anteriorly, inferiorly, and laterally with the disc
TMJ arthrokinematics of mouth closing, ipsilateral deviation, and RET
mandible rolls posteriorly
glides anterior, inferiorly and laterally with the disc
open packed position of the TMJ.
mouth slightly open, lips together, teeth are NOT in contact
