TMJ Arthrokinematics

Question 1

How many degrees of freedom in the TMJ?

Answer 1

3 Degrees
Depression/Elevation
Protrusion/Retrusion
Lateral Excursion

Question 2

The upper 1/2 of the TMJ is responsible for which movement?

Answer 2

Glide or translation of disc on the temporal surface

Question 3

The lower 1/2 of the TMJ is responsible for which movement?

Answer 3

Roll or rotation

Question 4

What are the Arthrokinematics of the TMJ during depression (opening)

Answer 4

1st part: Anterior Roll,

2nd part: Anterior/inferior Translation

Question 5

What percentage of opening comes from the translation

Answer 5

50-65%

Question 6

What percentage of opening comes from the roll

Answer 6

35-50%

Question 7

Describe the arthrokinematics of the TMJ during closing

Answer 7

1st part: Posterior/Superior Translation

2nd part: Posterior Roll

Question 8

What are the arthrokinematics during protrusion

Answer 8

Anterior Glide

Question 9

What are the arthrokinematics during retrusion

Answer 9

Posterior Glide

Question 10

Describe the arthrokinematics during lateral excursion

Answer 10

Ipsilateral mandibular condyle rotates/pivots laterally

Contralateral mandibular condyle translates anteriorly and rotates medially

Question 11

Whats the open pack for the TMJ

Answer 11

Teeth separated 2-3mm

Question 12

Closed pack position for the TMJ

Answer 12

Full occlusion

Question 13

Capsular pattern for the TMJ

Answer 13

inferior glide restricted

Question 14

ROM for TMJ

Answer 14

Depression: 40-55mm
Protrusion: 3-6mm
Retrusion: 3-4mm
Lateral Excursion: 10-12mm