TMJ

Question 1

The function of the disc is to __ joint cavity into 2 functional components.
Lower portion of joint capsule attaches __ __ to disc and upper portion of joint capsule attaches disc to __ __.

Answer 1

1) separate
2) mandibular condyle
3) temporal bone/mandibular fossa

Question 1

What part of the joint capsule is thin and what part is thickened & supported by collateral ligaments?

Answer 1

1) thin posteriorly and anteriorly
2) thickened laterally and medially & supported by collateral ligaments

Question 2

Label #1-5 in the picture.

Answer 2

Question 2

Upper joint of the TMJ is a __ __ joint for __ of mandible condyles. The lower joint of the TMJ is a __ joint that permits __ of condyles.

Answer 2

1) plane gliding joint
2) translation
3) hinge joint
4) rotation

Question 3

The disc is att. to TMJ’s joint capsule. What does the disc att. to posteriorly? What about anteriorly?

Answer 3

1) Posterior: retrodiscal lamina
2) Anterior: lateral pterygoid and anterior capsule

Question 4

T/F: If disc was posteriorly dislocated, the laminae may approximate b/w the mandibular condyle and fossa.

Answer 4

false; if disc was dislocated anteriorly this would be true.

remember this for DDWOR

Question 4

Function of retrodiscal laminae is to stabilize the __ and prevent excessive translation of disc over the __.

Answer 4

1) disc
2) condyle

Question 5

The __ __ is a ligament that extends from temporal bone to posterior disc. It contains Ns, vessels, and elastic fibers that aid is disc recoil during mouth (opening/closing).

Answer 5

1) retrodiscal laminae
2) closing

Question 6

The __ ligament thickens the ant. joint capsule and functions to prevent __ dislocation, prevent __ slippage of disc, and counter pull of __ __ muscle.

Answer 6

1) temporomandibular ligament
2) posterior dislocation
3) medial
4) lateral pterygoid

Question 7

Name the muscles of mastication (4).

Answer 7

Temporalis
Masseter
Medial Pterygoid
Lateral Pterygoid

Question 8

1) Which muscles help close the mouth?
2) Out of these muscles, which one(s) protrude the mandible in addition to elevating it?

Answer 8

1) Temporalis, masseter, & medial pterygoid
2) Medial pterygoid

Question 9

What muscle opens the mouth/depresses mandible, protrudes mandible, and can laterally deviate mandible unilaterally.

Answer 9

Lateral pterygoid

Question 10

Infrahyoid muscles __ the hyoid and suprahyoid muscles __ the hyoid. In addition to elevating the hyoid, the digastric muscle __ the mandible against resistance.

Answer 10

1) depress
2) elevate
3) depresses the mandible

Question 11

When the mouth opens, the first 50% of the motion occurs at the __ joint where the condyle __ in place. The last 50% of the motion occurs at the __ joint where the __ is pulled anteromedially by __ __. Then it slides fwd with the condyle.

Answer 11

1) lower joint
2) rotates/rolls
3) upper joint
4) disc
5) lateral pterygoid

Question 12

T/F: N branches of C1-C3 innervate suprahyoid muscles.

Answer 12

false, infrahyoid muscles

Question 13

What N innervates the muscles of mastication and supplies sensory from the temporal region, to the ears, to the inside of mouth/lower face/lower lip region?
What CN is this N a branch of?

Answer 13

Mandibular Nerve

CN 5 Trigeminal N

Question 14

What is the artery that has multiple arteries branching off of it to supply the TMJ joint?

Answer 14

External carotid A

Question 15

Review ROM norms for TMJ

Answer 15

Question 16

T/F: Only a very small
% of the US population experience TMD. Of those that do, most cases progress to chronic TMD.

Answer 16

False; 65-85% of pop. experience TMD. Only 5-12% progress to chronic TMD.

Question 16

What are the open-packed and close-packed positions for TMJ?

Answer 16

Open-packed/Resting: slight opening w/ tongue resting on roof of mouth

Close-Packed: fully closed

Question 16

T/F: Chronic TMD is more common in women.

Answer 16

True
Women: 8-15%
Men: 3-10%

Question 17

What are the categories of TMD? (3)

Answer 17

1) myofasial
2) disc displacement
2a) DD with reduction
2b) DD without reduction
3) Joint Dysfunctions: Degenerative/ Inflammatory

Question 18

Masticatory Muscle Disorders MOIs include __, __, __. They can result in decr. motion, altered occlusion, and __ points with __ pain.

Answer 18

1-3) strain (direct trauma), overuse injury (grinding, guarding), or centrally mediated pain
4) trigger points
5) Referred Pain
Pain referred to face, teeth, auricular area, temporal area, periocular area, & upper cervical area

Question 19

TTP to muscles, pain at endROM when muscle is __, pain w/ AROM/resistance, __ motion patterns, and pain w/ __ are signs of Masticatory Muscle Disorders.

Answer 19

1) stretched
2) aberrant
3) biting tongue depressor on ipsilateral side

Question 20

General findings for DD and joint dysfunction are ___ pain which is the common primary complaint, TTP joint line, and pain w/ test that place a ___ load on the joint.

Answer 20

1) pre-auricular 2) compressive

Question 21

What are 2 MOIs for joint dysfunction?

Answer 21

1) Macrotrauma 2) Microtrauma **can also lead to guarding**

Question 22

Disc displacement __ __ will present with clicking and intact joint motion. DD __ __ will present with limited mouth __ ROM and a __ sensation with opening/closing.

Answer 22

1) with reduction 2) without reduction 3) opening ROM 4) catching sensation

Question 23

1) 2 TMJ deviations are __ curve and __ curve. 2) Which curve is d/t DDWOR, muscle hypomobility, or joint hypomobility? 3) Which curve is d/t muscular imbalance or a medially displaced condyle “walks around the disc”?

Answer 23

1) C-type & S-type curves 2) C type 3) S type

Question 23

Early deviation causes __ and late deviation causes __/__ __.

Answer 23

1) spasms 2-3) capsulitis/tight capsule

Question 24

1) Describe how clicking occurs with DDWR. 2) What is reciprocal clicking?

Answer 24

1) Partial anterior displacement disc in resting position. Opening click indicates disc reduction as condyle passes over its posterior border. 2) Reciprocal clicking occurs with closing when condyle slips posteriorly over displaced disc.

Question 25

Describe DDWOR.

Answer 25

Disc no longer reduces and remains anteriorly displaced. Opening ROM may be limited. Compressive load places on retrodiscal lamina.

Question 26

Describe open lock.

Answer 26

At max opening, condyle moves over anterior rim of disc, leaving it posterior to condyle and outside the fossa. The disc prevents the condyle from slide back for closing. **may cause masseter and temporalis guarding**

Question 27

Closed lock occurs during DD ___. D/t DD, condyle is unable to pass over __ border of disc with __.

Answer 27

1) DDWOR 2) Posterior border 3) opening **disc remains bunched anterior to the mandibular condyle**

Question 28

What are 3 MOIs for Category 3 of TMD (degenerative / inflammatory)?

Answer 28

1) Degeneration: excessive loading, prolonged chemical irritation 2) Osteoarthritis: active inflammatory process 3) Osteoarthrosis: NO active inflammatory process

Question 29

What are some signs pt may present with during examination if pt has degenerative/inflammatory TMD? (3)

Answer 29

1) crepitus 2) uni or bilat S&S 3) deviation with opening, protrusion, & contralat deviation if TMD is unilateral.