Mandible

The mandible (lower jaw) is the only movable bone of the skull. It houses the lower teeth and provides the bony framework for the lower face. Through the temporomandibular joints (TMJ), it enables chewing (mastication), speech articulation, swallowing, and mouth opening. The masseter, medial pterygoid, temporalis, and lateral pterygoid muscles attach to it to drive these movements.

The mandible articulates exclusively with the temporal bones of the skull, forming the left and right temporomandibular joints (TMJ). These are the only synovial joints of the skull and are unique in having an articular disc (meniscus) dividing the joint space. The mandible does not articulate directly with any other bones; it is connected to the hyoid bone only via muscles and ligaments.

Mandibular fractures are among the most common facial fractures, frequently resulting from motor vehicle accidents, falls, or interpersonal violence. Common fracture sites include the condylar neck, symphysis/parasymphysis (chin region), and angle of the mandible. They often present with malocclusion (misaligned bite), pain, swelling, and trismus (inability to open the mouth). Treatment typically involves closed or open reduction with internal fixation.