Oral Surgery · single question
The TMJ (temporomandibular joint) disc divides the joint into how many compartments?
Show answer and explanation
Correct answer: D. 2 compartments (upper compartment: gliding; lower compartment: rotation/hinge)
- A. 3 or 4 compartments are incorrect — the TMJ disc creates exactly 2 compartments.
- B. See answer to A.
- C. 1 compartment is incorrect — the disc creates two distinct spaces with different types of movement.
- D. Correct. The articular disc (meniscus) of the TMJ divides the joint into TWO compartments: the SUPERIOR (upper) compartment — between the disc and the temporal bone, where gliding/translation occurs; and the INFERIOR (lower) compartment — between the disc and the condyle, where rotation/hinge movement occurs.