– A disorder of the temporomandibular joint structure characterized by pain, muscle spasm, and changes in jaw movement.
Causes and Incidence
Predisposing factors for temporomandibular joint (TMJ) disorders include congenital and developmental anomalies (agenesis); joint diseases (arthritis, ankylosis, neoplasms, or lupus); internal derangements of the intraarticular disk; fractures and dislocations from trauma; teeth grinding or clenching; and prolonged stress.
The precise pathophysiologic process is dictated by the predisposing factor. Congenital and developmental anomalies and fractures and dislocations produce a shift in the mandible and a severe malocclusion, which leads to asymmetric jaw movements, muscle spasms, and pain. Underlying disease processes lead to inflammation and infection in the joint, which limits jaw movement and causes pain. Teeth grinding and jaw clenching habits set up increased muscle tonus, which induces muscle fatigue and spasm.
Common signs and symptoms include muscle spasm and pain at the joint, temples, mandible, or masticatory muscles that worsens with jaw movement or finger pressure on the joint. Cracking, clicking, and popping sounds may occur with jaw movement. Pain may be referred to the neck and shoulders and may be accompanied by headache, tinnitus, and earache.
Freezing of the joint may be a complication.
To evaluate joint and determine predisposing factor
To evaluate bite
Computed tomography/ magnetic resonance imaging
To detect soft tissue abnormalities and degenerative changes
To assess degree of jaw dysfunction
Arthroscopy to debride joint, lyse adhesions, or reposition or remove disk if condition is unresponsive to more conservative management; jaw reconstruction to correct facial deformities and realign jaw; condylectomy to remove condyle; osteotomy to excise bony overgrowth.
Analgesics for pain; nonsteroidal antiinflammatory drugs; muscle relaxants for spasm; antianxiety agents if disorder is stress related.
Nightguard, bite plate to prevent grinding and clenching; splint to realign malocclusion; moist heat and ultrasound to induce muscle relaxation and enhance analgesia; cold to reduce muscle spasm and inflammation; jaw exercises to stretch muscles; biofeedback or relaxation exercises to relieve stress.