Question

The articular disc of the temporomandibular joint extends horizontally and therefore divides the joint cavity into two separate chambers. As a result, the temporomandibular joint is really two synovial joints: one between the temporal bone and the articular disc, and the other between the articular disc and the mandible.

Option 1:
The temporomandibular joint has a single synovial joint between the temporal bone and mandible.

Option 2:
The articular disc of the temporomandibular joint does not affect its structure.

Option 3:
The temporomandibular joint is a single synovial joint without division.

Option 4:
The temporomandibular joint consists of two synovial joints due to the horizontal extension of the articular disc.

Answer 1

The articular disc of the temporomandibular joint extends horizontally and therefore divides the joint cavity into two separate chambers. As a result is Option 4: The temporomandibular joint consists of two synovial joints due to the horizontal extension of the articular disc.

Step-by-step explanation:

The temporomandibular joint, commonly known as the TMJ, is a synovial joint that connects the mandible (lower jaw) to the temporal bone of the skull. The joint has a unique structure because of the presence of an articular disc that divides the joint cavity into two separate chambers.

The articular disc extends horizontally between the temporal bone and the condyle of the mandible, creating two synovial joints. The first synovial joint is formed between the temporal bone and the articular disc, while the second synovial joint is formed between the articular disc and the mandible. This division allows for the movements of the mandible, including elevation/depression, protraction/retraction, and side-to-side motions. Therefore the correct option is Option 4: The temporomandibular joint consists of two synovial joints due to the horizontal extension of the articular disc.