Temporomandibular joint disorders (TMJ), occur as a result of problems with the jaw, jaw joint, and surrounding facial muscles that control chewing and moving the jaw. Causes include injury to the jaw joint, grinding or clenching the teeth, dislocation of the soft cushion or disc between the ball and socket, and osteoarthritis or rheumatoid arthritis in the temporomandibular joint.

Symptoms

Symptoms of TMJ disorders may include:

  • Pain in and around the ear
  • Pain or tenderness of the jaw
  • Difficulty chewing or discomfort while chewing
  • Aching facial pain
  • Locking of the joint, making it difficult to open or close the mouth

TMJ disorders can also cause a clicking sound or grating sensation when you open the mouth or chew. But if there's no pain or limitation of movement associated with the jaw clicking, the patient probably doesn't need treatment for a TMJ disorder.

Causes

The exact cause of a person's TMJ disorder is often difficult to determine. The pain may be due to a combination of problems, such as arthritis or jaw injury. Some people who have jaw pain also tend to clench or grind their teeth, but many people habitually clench their teeth and never develop TMJ disorders.

Painful TMJ disorders can occur if:

  • The disk erodes or moves out of its proper alignment
  • The joint's cartilage is damaged by arthritis
  • The joint is damaged by a blow or other impact

In many cases, however, the cause of TMJ disorders is not clear.

Risk Factors

Temporomandibular joint disorders may occur as a result of an injury to or inflammation of the joint. Damage to the TMJ can result from the following:

  • Arthritis
  • Excessive teeth grinding (e.g., during sleep; called bruxism)
  • Jaw wound or trauma
  • Muscle tension
  • Poor posture
  • Repetitive stress

TMJ disorders most commonly occur in women between the ages of 20 and 40, but may occur at any age.

Complications

Generally the outlook is good. Most TMJ disorders improve over time and do not get worse. It is very rare to get any complications with this condition. Some people do have symptoms that last longer or recur, but even these can usually be improved with the treatments. Most people do not need injections or surgery and will get better with simple treatments and time.

Prevention

The following recommendations may help prevent temporomandibular joint disorders or may help prevent a recurrence of TMJ symptoms:

  • Avoid foods that are difficult to chew
  • Avoid excessive gum chewing.
  • Avoid biting pencils, pen caps, fingernails, and cuticles.
  • Learn relaxation techniques to reduce muscle tension and stress and improve sleep.
  • Maintain proper posture and learn about ergonomics.
  • Change positions regularly throughout the day and stretch periodically to relieve repetitive stress on the body.