TMJ disorder or temporomandibular joint disorder is a condition involving the inflammation of the joint at the angle of the jaw. It can also involve conditions affecting the muscles for mastication that can result to significant pain on the jaw area.

The temporomandibular joint is the structure connecting the mandible to the skull and also responsible for the opening and closing of the mouth. Wear and tear on the structures in the joint leads to the development of TMJ causing difficulties in using the jaw. TMJ disorder causes dysfunction to the person involved because of significant pain.

TMJ disorder was previously known as Costen’s syndrome from the person who characterized it in 1934.

Causes of TMJ Disorder

Causes of TMJ are vast including other conditions affecting the nearby structures of the jaw. Specific causes include:

• Bruxism
Bruxism or the involuntary or unconscious grinding of the teeth at night is a common cause of TMJ disorder. As the jaw is moved sideways to grind the teeth, the soft tissues may suffer wear and tear and may affect the overall joint.

• Physical trauma to the area
Direct physical trauma to the TMJ or the jaw can damage the supporting structures in the area leading to inflammation and pain. Physical trauma may include direct blow to the face, whiplash injury and fracture in the jaw area.

• Bite collapse
The loss of bite height causes the lower jaw to be positioned unnaturally during mastication or chewing contributing to TMJ disorder.

• Degenerative joint disorders
Osteoarthritis, ankylosis, and other pathologic conditions of the TMJ also contribute to the disorder as a result of the organic degeneration of the soft tissues in the joint.

• Stress
Stress can also be a cause of TMJ disorder as a result of clenching and anger that puts tension on the jaw.

• Dental problems
Defective crowns, genetic dental problems, poor restoration and lack of cooperation during any dental treatment may also cause a misalignment of the teeth causing TMJ disorder because of increased burden on the mandible.

Symptoms of TMJ Disorder

The clinical manifestations of TMJ disorder vary from person to person depending on the presentation. Symptoms usually arise from problems in the nerves, muscles, tendons, bones, teeth, connective tissue and ligaments around the jaw. Symptoms can be both localized in the jaw area or can extend to adjacent structures. Common symptoms include:

• Difficulty in chewing
• Pain or discomfort along the jaw
• Dull pain on the face
• Recurrent headaches (migraine-like) and earache in the morning
• Difficulty to open and close the mouth
• Popping sound while opening and closing the mouth
• Dizziness
• Pain in the neck and shoulder area
• Blinking

The pain experienced in TMJ disorder does not really originate on the joint itself because cartilage does not contain any pain receptors. Pain usually arises from the adjacent tissues such as the muscles and the nerves. Along the joint area, the trigeminal nerve passes through it going to the brain making it one of the major sources of discomforts.

Since TMJ disorders involve various etiologies, the treatment option may also involve more than one discipline such as orthopedics, neurology and dental health.