Temporamandibular Joint Flashcards Preview

Temporal region > Temporamandibular Joint > Flashcards

Flashcards in Temporamandibular Joint Deck (22)
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1
Q

What is the TMJ?

A

articulation of the condyle of the mandible with the zygomatic part of the temporal bone.

2
Q

What sits on the inferior surface of the zygomatic process?

A

condyle of the mandible sits in the mandibular fossa.

3
Q

What holds the mandible in the mandibular fossa?

A

Two humps:
postglenoid tubercle
articular eminence

4
Q

Where is the postglenoid tubercle?

A

posterior to the mandibular fossa

5
Q

Where is the articular eminence?

A

anterior to the mandibular fossa

6
Q

What important ligaments holds the TMJ together?

A

Temporomandibular ligament (lateral ligament)
Sphenomandibular ligament
Stylomandibular ligament

7
Q

Where is the Tempromandibular ligament (lateral ligament) ?

A

lateral thickening of the temporomandibular joint

capsule,

8
Q

What is the function of the temperomandibular ligament (lateral ligament) ?

A

acts with the postglenoid tubercle to resist posterior dislocation of the TMJ

9
Q

Where is the Sphenomandibular ligament located?

A

from the spine of the sphenoid to the lingula of the

mandible

10
Q

What is the purpose of the Sphenomandibular ligament?

A

This ligament is a swinging hinge for the mandible, serving both as a fulcrum and a check ligament. It also supports the weight of the mandible, along with the temporalis muscle.

11
Q

Where is the Stylomandibular ligament?

A

from the styloid process to the angle of the mandible,

12
Q

What is the Stylomandibular ligament?

A

a thickening of the fibrous capsule of the parotid gland.

13
Q

What type of joint is the TMJ?

A

modified hinge type of synovial jointbetween the head of the condyle of the mandible and the mandibular fossa and articular eminence of the temporal bone.

14
Q

What does the articular disc of the TMJ divide?

A

temporomandibular joint into two separate joints, each lined by its own synovial membrane and each with a different motion:

15
Q

What are the compartments of the TMJ?

A

superior

inferior

16
Q

What does the Superior compartment of the TMJ permits?

A

anteroposterior translation of the mandible.

17
Q

What does the inferior compartment of the TMJ permits?

A

hinge motions of elevation and depression of the

mandible.

18
Q

What are the three motions of the TMJ?

A

elevation/depression (open/close),
lateral excursion (side to side),
protrusion/retrusion (protraction/retraction).

19
Q

What are the movements of the TMJ during chewing and speaking?

A

combination of all three motions

20
Q

What does initial depression of the jaw consist of?

A

opening just enough to separate the maxillary and mandibular teethoccurs as a hinge motion in the inferior compartment of the TMJ. Elevation of the jaw across this small distance is also a hinge motion.

21
Q

What does depressing the jaw widely consist of?

A

involves translation of the mandibular condyle and articular disc anteriorly onto the articular eminence. This motion occurs in the superior compartment of the TMJ. The mandibular condyle slides back again into the mandibular fossa in normal jaw closing. This means that for all but minimal elevation/depression, protrusion/retrusion must also occur.

22
Q

What does lateral excursion of the jaw consist of?

A

unilateral protrusion, which can be accomplished by muscles pulling on the condyle on the same side of the excursion (ipsilateral contraction) or by muscles pulling on the opposite side of the excursion (contralateral contraction).