TMJ & Occlusion

Question 1

Type of cartilage surrounding TMJ

Answer 1

Thick avascular fibrous CT (NOT HYALINE like every other joint)

Question 2

Which portion of TMJ is thick bone?

Answer 2

articular eminence

Question 3

In the lower compartmet of the TMJ, _______ occurs.

In the upper portion, _______ occurs

Answer 3

lower rotation

upper translation

Question 4

Imaging the TMJ:
_______ can observe bony structures
_______displays hard tissue well
_______ Gold standard of imaging. Can show disc

Answer 4

Radiograph
CAT Scan
MRI

Question 5

The _______ ligament(s) attach the disc to the head of the condyle and restrict movement of the dic away from the condyle. Also divide the TMJ into superior and inferior cavities, each filled with synovial fluid.

Answer 5

Collateral Ligaments

Question 6

The _______ ligament prevents lateral movements of TMJ, retains and secretes synovial fluid.

Answer 6

capsular ligament

Question 7

The main stabilizing ligament of TMJ preventing posterior and inferior displacement and limits rotational opening of jaw.

Answer 7

Temporomandibular ligament

Question 8

Ligament that initiates translation of condyle down articular eminence and limits posterior movement to protect retrodiscal tissue

Answer 8

temporomandibular ligament

Question 9

Ligament limits excess opening of mandible and attaches lingula to sphenoid spine

Answer 9

sphenomandibular ligament

Question 10

Ligament that limits excessive protrusion and attaches to angle of mandible.

Answer 10

stylomandibular ligament

Question 11

Nerve that innervates TMJ

Answer 11

auriculotemporal

Question 12

Nerve that provides motor and sensory innervation to mm of TMJ

Answer 12

Trigeminal

Question 13

MM that elevates and retrudes mandible

Answer 13

temporalis

Question 14

MM that elevates and protrudes mandible

Answer 14

Medial pterygoid

Question 15

MM is inactive when closing jaw

Answer 15

inferior lateral pterygoid

Question 16

MM moves articular disk forward, does not elevate the mandible, and positions the condyle and disk against the eminence during closing.

Answer 16

superior lateral pterygoid

Question 17

MM elevates the hyoid bone and depresses the mandible

Answer 17

Anterior and posterior digastric

Question 18

All infrahyoid mm are innervated by the ansa cervicalis except

Answer 18

thyrohyoid- C1 via hypoglossus

Question 19

All Extrinsic mm of the tongue are innervated by CN12 except

Answer 19

palatoglossus- CNX

Question 20

Centric relation is when

Answer 20

the condyle is most superior and midmost position

Question 21

70% of the population has this class of occlusion

Answer 21

class
1st molar MB cusp centered
Molar and canine centered

Question 22

25% of the population has this class of occlusion

Answer 22

class 2
mandible positioned distally

Question 23

5% of the population has this class of occlusion

Answer 23

class 3
mandible position mesially

Question 24

class 1 occlusion is defined as

Answer 24

the mesial buccal cusp of max. 1sr molar lying betwwen MB groove of mandib 1st molar
&
Max canine lying between mandib, 1st premolar and canine

Question 25

Working cusps on maxilla

working on mandible

Answer 25

max-lingual

man- buccal

Question 26

Non working cusps tend to be

Answer 26

sharper, no contact, and oppose grooves and embrasures

Question 27

In general a _______tooth contacts its counter part and the posterior tooth opposing it

Answer 27

maxillary

Question 28

In the intercuspal position, the cusp tip of the permanent max canine is in direct alignment with which anatomic feature of the mandibular teeth?

a. incisal embrasure
b. facial embrasure
c. interproximal space

Answer 28

Facial embrasure