The mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the face.It forms the lower jaw and holds the lower teeth in place. The mandible sits beneath the maxilla. The bone is formed from a fusion of left and right processes, and the point where these sides join, the mandibular symphysis, is still visible as a faint ridge in the midline. Like other symphyses in the body, this is a midline articulation where the bones are joined by fibrocartilage, but this articulation fuses together in early childhood.