What is Temporomandibular joint syndrome?

Temporomandibular joint (TMJ) disorder is not a single condition but rather a group of symptoms that often include:

• Pain in the hinges that connect the lower jaw to the skull (temporomandibular joints)
• Headaches
• Earaches
• Limitations in jaw movement
• Clicking or popping sounds as the jaw moves
• Eye pain
• Neck pain, back pain or shoulder pain

Some estimates indicate that more than 10 million Americans suffer from TMJ disorder, according the National Institute of Dental and Craniofacial Research, part of the National Institutes of Health (NIH). This disorder is a complex and poorly understood group of conditions that can lead to pain in the jaw joints and surrounding muscles and other soft tissues.

TMJ disorder, also called TMD, is a common cause of orofacial pain. Patients often report pain while chewing as this disorder is often aggravated by movement of the jaw.

The muscles used during mastication (chewing) are part of the temporomandibular joints. A temporomandibular joint is located in front of each ear. Each temporomandibular joint connects the lower jawbone (mandible) to the skull. The bony surfaces of these joints are covered with cartilage and separated by small discs that prevent the bones from rubbing together. The temporomandibular joint is used for many functions, including biting, chewing, swallowing, speaking and facial expressions. TMJ disorder can thus affect a patient’s ability to speak, eat, swallow, chew and breathe.

Generally, the group of conditions known as TMJ disorder falls into three main categories:

• Myofascial pain, which includes pain related to the function of the jaw and may include the muscles of the neck and shoulders.
• Internal derangement of the joint, which includes either a dislocated jaw or a possible misalignment of the disc that provides a buffer between the skull and lower jaw.
• Arthritis, which can inflame the jaw joints. Several forms of arthritis can cause symptoms of TMJ disorder, including osteoarthritis (OA), rheumatoid arthritis, infectious arthritis, traumatic arthritis and gout.

The cause of TMJ disorder is unknown. However, researchers note that the majority of people affected are women in their childbearing years. Notably, many people with TMJ disorder also have other health concerns ranging from fibromyalgia and sleep disorders to irritable bowel syndrome and a heart condition called mitral valve prolapse. The relationships between these health concerns and TMJ disorder are not clearly understood and require further investigation.

How is it diagnosed?

Diagnosis of temporomandibular joint (TMJ) disorder begins with a medical history and a physical examination of the patient. The physician or dentist will look for pain or tenderness in the jaw joints and chewing muscles, examine the jaw during movement for clicking or popping sounds, and observe for locking of the jaw or limited motion while opening.

During the physical examination, the patient may have a noticeable deviation of the lower jaw (mandible) when opening or closing the mouth. In some cases, the patient’s ability to open or close the mouth is severely limited. There are other possible causes of orofacial pain that must be ruled out before a diagnosis of TMJ disorder can be made, including:

• Congenital abnormalities
• Tumors
• History of trauma to the face

Depending on the findings of the medical history and physical examination, some physicians may order panoramic x-rays or MRI is an imaging test used in pain diagnosis, to guide treatment and to monitor for relapse.other specialized x-ray tests, such as arthrography, a joint imaging test using a special dye. MRI (magnetic resonance imaging) is used in rare cases where the physician suspects an underlying cause of arthritis or internal joint derangement. Radionuclide imaging can help detect a variety of bone diseases, such as tumors or osteomyelitis (bone infection).

It is not uncommon for many conditions to be ruled out before a diagnosis of TMJ disorder is made. Many patients will see several healthcare providers, including primary care physicians, dentists, sleep specialists, neurologists, endocrinologists, rheumatologists, pain specialists, chiropractors, ear, nose and throat (ENT) specialists or oral and maxillofacial surgeons in their search for a definitive diagnosis of the cause of their symptoms.

In order to make a proper diagnosis, it is recommended that the patient be prepared to describe symptoms and answer questions regarding the pain, such as those on a pain assessment, including:

• What kind of pain is it (e.g., stabbing, aching, throbbing or sharp)?
• Does the pain come and go, or is it constant?
• Is there anything that alleviates the pain?
• Is there anything that aggravates the pain?
• On a scale of 1 to 10, what is the intensity of pain?
• Is there any evidence of teething grinding at night?
• Does the patient bite the nails, chew on pencils or chew a lot of gum?

How are temporomandibular joint disorders treated?

Painful musculoskeletal conditions, including temporomandibular joint (TMJ) disorder, require evaluation from a qualified physician or dentist who can offer treatment options. There is no standard treatment method. Patients are often directed to find relief using a tailored regimen of one or more of the following options:

• Rest for the jaw.
• Application of heat to tender areas (thermotherapy). This may include ultrasound therapy, a method of applying deep heat to tissues using high-frequency sound waves.
• Application of cold packs or ice bags to tender areas (cryotherapy).
• Physical therapy. The treatment of physical dysfunction or injury with the use of special exercises, techniques and devices.
• A diet of soft foods.
• Stress reduction.
• Low doses of nonsteroidal anti-inflammatory drugs (NSAIDs) for two weeks.
• Anti-anxiety medications (anxiolytics) and muscle relaxants.
• Injection therapy. Injections of corticosteroids may reduce pain and improve the jaw joints’ range of motion in cases caused by arthritis. In addition, trigger point injections of medication directly into a specific location may relieve pain.
• Interocclusal appliances (e.g., a plastic biteplate that helps align the upper and lower jaws or a night guard to prevent nighttime teeth grinding).
• Behavior modification (e.g., biofeedback, cognitive behavioral therapy).
• Arthrocentesis. Removal of fluid from a joint.
• Arthroscopy. The direct visualization of the interior of a joint by means of an arthroscope inserted into the joint through a small incision in the skin. An arthroscope is a small tubular instrument that contains a light and small camera attached to a close-circuit monitor that displays an enlarged real-time image and can be used in minimally invasive surgery.

These therapies often provide at least some measure of relief for the painful symptoms, either alone or in various combinations. The specifics of a particular patient will help guide treatment options. If the patient does not respond to any less-invasive treatments, surgery to realign the jaw, a joint replacement (arthroplasty) or joint implant may be recommended in severe cases. The surgical replacement of jaw joints is risky and may cause permanent damage to the jaw. Dental surgery to alter a patient’s bite is irreversible and may not offer the patient any pain relief.

There are no known ways to prevent TMJ disorder beyond maintaining good oral hygiene and good posture, wearing protective face masks during contact sports and avoiding habits such as nail biting, chewing on pens or pencils, eating hard food, or excessive gum chewing. It should be noted that experts disagree on whether bad oral habits are a possible cause of this condition.

Maintaining a pain diary when symptoms flare up will help a patient monitor the condition over time. It will also help to detail specific information about the pain that may help the physician determine appropriate treatment options.

Medications

• For minor pain, you may use non-prescription drugs, such as aspirin or acetaminophen.

Valium (Diazepam), Motrin (Ibuprofen), Aleve (Naprosyn)

What might complicate it?

The following conditions may complicate the diagnosis: arthritis, pain disorders affecting the nervous system, blood or immune system disturbances.

Predicted outcome

Joint pain or discomfort may persist and proceed until dental care, stress reduction, and muscle tension relief is obtained. Most people with TMJ disorders respond well to conservative medical treatment and self care over time.

Alternatives

Myofascial pain syndrome, tumor, and arthritic conditions may present with similar symptoms.

Appropriate specialists

Neurologist, dentist, oral surgeon, and otorhinolaryngologist.

Last updated 25 June 2015