About Temporomandibular Disorders

What are TMJ disorders?
Temporomandibular joint and muscle disorders, commonly called "TMJ," are a group of conditions that cause pain and dysfunction in the jaw joint and the muscles which control jaw movement. One or both joints may be affected in people with TMJ disorders, which can affect a person’s ability to speak, eat, chew, swallow, make facial expressions, and even breathe.

Researchers generally agree that the conditions fall into three main categories:

  • Myofascial pain, the most common, involves discomfort or pain in the muscles that control jaw function.
  • Internal derangement of the joint involves a displaced disc, dislocated jaw, or injury to the condyle.
  • Arthritis refers to a group of degenerative/inflammatory joint disorders that can affect the temporomandibular joint.

A person may have one or more of these conditions at the same time. People diagnosed with TMJ disorderss may also experience other symptoms and medical conditions as part of broader multi-systems illnesses which go unrecognized. Patients with TMJ disorders are most often diagnosed and treated primarily by dentists or oral surgeons, while another medical professional may be treating them for other conditions.

What are the causes of TMJ disorders?
Trauma to the jaw or temporomandibular joint plays a role in some TMJ disorders. But for most jaw joint and muscle problems, scientists don’t know the cause. For many people, symptoms seem to start without obvious reason. Research disputes the popular belief that a bad bite or orthodontic braces can trigger TMJ disorders. Because the condition is more common in women than in men, scientists are exploring a possible link between sex hormones and TMJ disorders.

There is no scientific proof that clicking sounds in the jaw joint will lead to serious problems. In fact, jaw clicking is common in the general population. Jaw noises alone, without pain or limited jaw movement, do not indicate a TMJ disorder and do not warrant treatment.

The roles of stress and tooth grinding as major causes of TMJ disorders are also unclear. Many people with these disorders do not grind their teeth, and many long-term tooth grinders do not have painful joint symptoms. Scientists note that people with sore, tender chewing muscles are less likely than others to grind their teeth because it causes pain. Researchers also found that stress seen in many persons with jaw joint and muscle disorders is more likely the result of dealing with chronic jaw pain or dysfunction than the cause of the condition.

What are the symptoms of TMJ disorders?
A variety of symptoms may be linked to TMJ disorders. Pain, particularly in the chewing muscles and/or jaw joint, is the most common symptom. Other likely symptoms include:

  • dull aching pain in the face, jaw, neck, or shoulders
  • jaw muscle stiffness
  • limited movement or locking of the jaw
  • painful clicking, popping or grating in the jaw joint when opening or closing the mouth
  • a change in the way the upper and lower teeth fit together or a bite that feels 'off'

Who gets TMJ disorders?
Over 35 million Americans are affected. Both men and women experience TMJ disorders, however, 90% of those seeking treatment are women in their childbearing years.

How are TMJ disorders diagnosed?
Currently there is no scientifically validated test available to correctly diagnose TMJ disorders. Because the exact causes and symptoms are not clear, identifying these disorders can be difficult and confusing. Currently, diagnosis is based on a patient’s description of symptoms, history and examination of the head, neck, face, and jaw.

If you suspect that you have a TMJ problem or are diagnosed with one, we suggest you initially consult your primary care physician to rule out other illnesses as a cause of your symptoms. Facial pain can be a symptom of many other conditions, such as a sinus or ear infections, various types of headaches, facial neuralgias (nerve-related facial pain), and even tumors. Ruling out these problems first helps in identifying TMJ disorders.

How are TMJ disorders treated?
For most people, discomfort from TMJ disorders will eventually go away without treatment. Simple self-care practices are often effective in easing symptoms.

If treatment is needed, it should be based on a reasonable diagnosis, be conservative and reversible, and customized to your special needs. Conservative treatments do not invade the tissues of the face, jaw, or joint, or involve surgery. Avoid treatments that can cause permanent changes in the bite or jaw.

Because there is no certified specialty for TMJ disorders in either dentistry or medicine, finding the right care can be difficult. The National Institutes of Health brochure on TMJ disorders recommends that you "look for a healthcare provider who understands musculoskeletal disorders (affecting muscle bone and joints) and who is trained in treating pain conditions. Complex cases, often marked by prolonged, persistent and severe pain; jaw dysfunction; co-existing conditions; and diminished quality of life, likely require a team of experts from various fields, such as neurology, rheumatology, pain management and others, to diagnose and treat this condition."

What conditions can overlap with TMJ disorders?
Some people have other health conditions that may co-exist with TMJ disorders, such as:

There are also many conditions that may produce similar signs and symptoms as TMJ disorders (pain and/or jaw dysfunction) and can lead to misdiagnosis include:

  • atypical (vascular) neuralgia
  • hypo- and hyperkinesia (abnormal jaw movements)
  • Lyme disease
  • myositis (muscle inflammation)
  • myositis ossificans (calcification in a muscle)
  • otitis (earache)
  • parotitis (salivary gland inflammation)
  • scleroderma (chronic hardening of the skin)
  • sinusitis
  • temporal arteritis (inflammation of the temporal artery)
  • toothache
  • trigeminal neuralgia
  • Trotter’s syndrome (nasopharyngeal carcinoma)

For more information about TMJ disorders, please visit www.tmj.org.