Acquired Abnormalities of the Temporomandibular Joint.

Mandibular growth is a complex process that involves the "functional matrix," an interaction of the muscles of mastication, occlusion, and jaw function. Although not a typical growth center, the mandibular condyle has a significant effect on the ultimate size, shape and function of the mandible and secondarily on overall facial form. Acquired temporomandibular joint (TMJ)/condylar abnormalities, such as juvenile idiopathic arthritis, idiopathic condylar resorption, TMJ ankylosis, and condylar hyperplasia, often result in facial deformity and functional deficits. Accurate diagnosis is critical for the clinician to assess potential progression of deformity, predict prognosis, and plan treatment.