Temporomandibular disorders (TMD), commonly called TMJ, are a complex and poorly understood set of conditions characterized by pain in the jaw joint and surrounding tissues as well as limitation in jaw movements. Injury and other conditions that routinely affect other joints in the body, such as arthritis, also affect the temporomandibular joint. One or both joints may be involved, and depending on the severity, they can affect a person's ability to speak, eat, chew, swallow, make facial expressions, breathe, and cause pain.
Also included under the heading of TMD are conditions involving the jaw muscles. These may accompany the jaw joint problems or occur independently. They are often confused with jaw joint problems because they produce similar signs and symptoms.
Researchers have found that temporomandibular disorders often occur along with other - and often painful - conditions in other parts of the body, prompting studies in search of a common factor underlying them all. Among these conditions are chronic fatigue syndrome, chronic headache, endometriosis, fibromyalgia, interstitial cystitis, irritable bowel syndrome, sleep disorders, and vulvodynia. Moreover, certain medical conditions, such as Ehlers-Danlos syndrome, dystonia, Lyme disease, and scleroderma, may affect the temporomandibular joint.
Approximately 35 million people in the United States suffer from TMJ problems at any given time. While both men and women experience these disorders, the majority of those seeking treatment are women in their childbearing years. The ratio of women to men increases with the severity of symptoms, approaching 9 to 1 for patient with major limitations in jaw movements and chronic, unrelenting pain.
Although the cause of most of these disorders is unknown, there are some known contributing factors to the development of these disorders. Among them are:
Genetic, hormonal, and environmental factors can also increase the risk for TMD. Studies have shown that a particular gene variant increases sensitivity to pain, and this variant has been found to be more prevalent among TMJ patients than among the populations at large. The observation that TMD are commonly found in women in their childbearing years has also led to research to determine the role of female sex hormones in these disorders. Environmental factors such as habitual gum chewing or sustained jaw positions may also contribute to TMD.
At present, there is no widely accepted, standard diagnostic test to identify all TMD. Because the exact cause and symptoms are not clear, identifying these disorders can be difficult and confusing. The American Association for Dental Research (AADR) recommends that a diagnosis of TMD or related orofacial pain conditions should be based primarily on information obtained from the patient's history and a clinical examination of the head and neck.
In addition to a detailed history and a careful clinical examination, imaging studies of the teeth and jaws may sometimes be helpful as a diagnostic tool. These include: routine dental x-rays and panoramic radiographs, computed tomography (CT or CAT scan), magnetic resonance imaging (MRI), and scintigraphy (bone scan).
Blood tests are sometimes recommended to rule out possible medical conditions as a cause of the problem.
Before undergoing any costly diagnostic test, it is always wise to get an independent opinion from another health care provider of your choice and one unassociated with your current provider.
The pain of TMD is often described as a dull, aching pain comes and goes in the jaw joint and nearby areas. However, some people report no pain but still have problems using their jaws. Symptoms can include:
Less common symptoms include: ringing in-the ears (tinnitus), dizziness, and vision problems.
Note: Jaw noises unaccompanied by pain or decreased mobility do not mean you have a TMD problem.
Keep in mind that occasional discomfort in the jaw joint or chewing muscles is common and is not always a cause for concern. Many people with TMD get better without treatment. Often, the problem goes away on its own in several weeks to months. However, if the pain is severe and lasts more than a few weeks, see your health care provider.
If you think you have a TMD, you may want to see a medical doctor to rule out some of the conditions that may mimic a TMD. For example, facial pain can be a symptom of many conditions, such as sinus or ear infections, decayed or abscessed teeth, various types of headache, facial neuralgia (nerve-related facial pain), and even tumors. If the medical doctor or your dentist gives you a diagnosis of a TMD, it is recommended that you consult our website for guidance regarding treatment.
There is no medical or dental specialty of qualified experts trained in the care and
treatment of TMJ patients. As a result, there are no established standards of care in clinical practice. Although a variety of health care providers advertise themselves as “TMJ specialists,” the more than 50 different treatments available today are based largely on beliefs, not on scientific evidence. Sir William Osler, the father of modern medicine, said that when there are many treatments for a single condition, it is because none of them work.
Because there is no certified specialty in treating TMD in either dentistry or medicine, finding the right care can be difficult. The National Institutes of Health advises patients to look for a health care provider who understands musculoskeletal disorders (affecting muscle, bone and joints) and is trained in treating pain conditions. Pain clinics in hospitals and universities are often a good source of advice, particularly when pain becomes chronic and interferes with daily life. Complex cases, often marked by chronic and severe pain, jaw dysfunction, comorbid conditions, and diminished quality of life, will likely require a team of doctors from fields such as neurology, rheumatology, pain management and others to diagnose and treat this condition.
Most people with TMD have relatively mild or periodic symptoms that may improve on their own within weeks or months with simple home therapy. Self-care practices, such as eating soft foods, applying ice or moist heat, and avoiding extreme jaw movements (such as wide yawning, loud singing, and gum chewing) are useful in easing symptoms.
Scientists strongly recommend treating TMD with the most conservative approaches possible. These are treatments that do not cause permanent changes in, or change the structure or position of, the jaws or teeth. Even when these disorders have become persistent, most patients still do not need aggressive types of treatment.
If your problems get worse with time, you should seek professional advice. However, first and foremost, educate yourself. Informed patients are better able to communicate with health care providers, ask questions, and make knowledgeable decisions. For information and guidance regarding treatment, read through our Treatment Section.
Patients who are told they should undergo treatment(s) to prevent the development of a TMD problem should know that there is currently no evidence that such conditions can be prevented.
Many medical and dental insurance plans do not pay for treatment of TMD or only pay for some procedures. Until the causes of these disorders have been discovered, and there are scientifically validated safe and effective treatments, insurance companies will not pay for treatments that have questionable outcomes. Contact your insurance company to determine treatments that are covered.
There are no standardized costs for TMD treatments.
The science on TMD is in its infancy and has yet to answer fundamental questions on the causes and risk factors or develop safe and effective treatments and cures. As research advances to understand more about the temporomandibular joint and its associated tissues, many in the health care community are reassessing past treatments and ways in which they were developed. A growing consensus considers TMD a complex family of conditions like hypertension or diabetes. In that regard, the TM disorders patient should be seen as a whole individual subject to a host of genetic, hormonal, environmental and behavioral factors that contribute to his or her state of health or disease. With that perspective, TMD cease to be isolated conditions limited to the teeth and jaws but rather conditions that may coexist with a range of other systemic pain conditions.
There is increasing evidence from research, as well as information compiled by patient health advocacy organizations, that patients with a given chronic condition often experience one or more additional chronic (and often painful) conditions. Among conditions found to overlap with TMD are chronic fatigue syndrome, chronic headache, endometriosis, fibromyalgia, interstitial cystitis, irritable bowel syndrome, sleep disorders, and vulvodynia, which are all disorders that are poorly understood. In some cases, a patient may experience one condition initially and then go on to develop another or others. In other cases, two conditions may occur together at the outset. Such a perspective can direct and inspire scientists to discover commonalities that can advance understanding and ultimately lead to beneficial therapies. Research to understand why these conditions coexist has only recently begun.