Mastication - LO 2

2. What type of joint is the temporomandibular joint (TMJ)? What actions occur at this joint?

The temporomandibular joint (TMJ) is a compound synovial hinge joint formed by the mandibular fossa of the temporal bone receiving the condyle of the mandible. These structures are separated by a fibrocartilaginous articular disc, which compounds the articulation into superior and inferior joints (and cavities).

The superior joint allows for protrusion and retraction of the mandible, while the inferior joint allows for elevation and depression of the mandible with minor pivoting actions. The muscles of mastication produce the movements at the TMJ. The TMJ is primarily afferently innervated by the auriculotemporal n. and vascularized by branches from both the maxillary a. and the superficial temporal a.