A ramus terminates as two processes: posteriorly, the condylar process (4), which lies in the glenoid fossa of the temporal bone and is separated from it by a meniscus (the temporomandibular joint) ; and anteriorly, the coronoid process (5), to which the temporal muscle is attached.

Numerous prominences and strongly reinforced areas that anchor muscles characterize the mandible, as do depressions that accommodate glands and muscles. On its outer surface, the mandible is thickest at the mental protuberance (6), or chin. This area is triangular in shape; its base projects bilaterally as the mental tubercles (7) and its ascending sides slope upward toward the dental arch. Within the curve of the slope is the mental fossa (8), pierced by a few small openings for blood vessels and nerves.

Below the dental arch, usually between the first and second pre-molars, is the mental foramen (9) . Here the bulk of the mental vascular bundle passes out the mandibular canal into soft tissues. Lesser branches continue anteriorly within bone in the incisive canal. Whereas the mandibular canal is a distinct channel within the bone, the incisive canal diminishes, almost disappearing, as it nears the midline.

The mandibular angle (10), also a heavily reinforced area, is irregularly shaped and serves as an attachment site for the masseter and medial (internal) pterygoid muscles.

The inner surface of the mandible is highly irregular in shape, with numerous depressions and prominences. Anteriorly and inferiorly on each side of the midline is the digastric fossa (11) , a shallow, elongated oval depression. Superior to the fossa, and closer to the midline, is the geniohyoid, or genial tubercle (12). This prominence may be a single, rather sharp prominence or, more commonly, two bilateral prominences. Occasionally the tubercle is divided into superior and inferior portions. When healthy teeth are present, this landmark is located below the apices of the incisors. After extensive bone resorption, the tubercle may be higher than the residual crest.

The mylohyoid line (13), originating in the third molar region and extending forward to terminate on the inner surface of the chin between the digastric fossa and the genial tubercle, is irregularly prominent. It is the crest of a pronounced ridge that juts bulkily from the body in most mandibles until at least the premolar area. Here it may begin to blend into the overall horseshoe shape of the body until its more anterior portion is indistinguishable, or it may continue as an obvious feature until it terminates between

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