Chapter 19 - Biomechanics of the mandible and current evidence base for treatment of the fractured mandible

Abstract

The mandible or lower jaw is the largest and strongest bone of the face, and it articulates with the skull at the temporomandibular joint. The mandible consists of a horseshoe-shaped body and a pair of rami. The body of the mandible meets the ramus on each side at the angle of the mandible. The body of the mandible, on its external surface in the midline, has a faint ridge indicating the line of fusion of the two halves during development at the mental symphysis. The mental foramen can be seen below the second premolar tooth; it transmits the terminal branches of the inferior alveolar nerve and vessels. On the medial surface of the body of the mandible in the median plane are seen the mental spines; these give origin to the genioglossus muscles above and the geniohyoid muscles below. The mylohyoid line can be seen as an oblique ridge that runs backward and laterally from the area of the mental spines to an area below and behind the third molar tooth. The submandibular fossa, for the superficial part of the submandibular salivary gland, lies below the posterior part of the mylohyoid line. The sublingual fossa, for the sublingual gland, lies above the anterior part of the mylohyoid line.