Gender-related pain: Temporomandibular Disorders
by Jennifer Wider, M.D.

(Washington DC):  An estimated 10 million Americans suffer from pain in their jaw joint and chewing muscles, a group of conditions known as temporomandibular disorders (TMD). Similar to other pain conditions, TMD affects women two times more than men, and is most prevalent between the ages of 20-40. For most patients, the pain is transient and can disappear without treatment. For a small number of patients, however, the problem is chronic and can have serious and life-altering consequences.

"Almost all pain conditions affect women more than men," explains Dr. Christian Stohler, professor and dean of the College of Dental Surgery at the University of Maryland. In addition, "pain conditions affect women in their childbearing years more often than afterwards and it has been shown that post-menopausal estrogen increases the pain of these conditions," according to Dr. Stohler. In other words, because the onset of TMD occurs more commonly after puberty, peaks in the reproductive years and is exacerbated by estrogen supplements, there is a potential link between pain disorders and female hormones.

Researchers have been examining data in an attempt to determine what makes women more vulnerable to chronic pain conditions. Studies have shown that women are affected by several pain conditions including fibromyalgia, lupus and rheumatoid arthritis more frequently than men. Findings from research conducted by Jon Levine, MD, PhD, professor of medicine at the University of California at San Francisco, point to areas of the brain where women react differently than men to pain signals. Levine and colleagues continue to explore the relationship between sex hormones and pain perception in the brain to try to understand the extreme differences between the sexes.

The underlying cause for temporomandibular disorders is not entirely understood. Most oral health professionals would agree that severe injury to the jaw joint or muscles can result in TMD, as well as arthritis of the joint and chronic clenching and grinding of the teeth; other potential causes are disputed by the medical community. Some experts suggest that dental procedures or malocculsion (bad bite) can trigger TMD. Others propose that stress can cause or irritate the condition.

Symptoms vary from patient to patient, but pain in the joint and/or surrounding muscles is most common. Limitation of jaw function, radiating pain in the eyes, face and neck and jaw-clicking or popping are other prevalent manifestations. Some patients experience headaches, dizziness and hearing problems. Others have more severe symptoms: nausea, extreme headaches, sleep disturbances and facial swelling. Diagnosis can be delayed because the characteristics of TMD may resemble other medical conditions.

Currently, there is no standard test to diagnose temporomandibular disorders. According to Dr. Stohler, "The diagnosis is driven by the patient's complaints. The doctor must match the physical complaint to pain and tenderness in the affected area." A simple physical exam of the face and jaw can provide enough information to make the correct diagnosis and start any necessary treatment. X-rays are rarely used and usually only when an underlying condition like arthritis is suspected.

Most TMD problems are temporary and will resolve with conservative therapies. Some health professionals will recommend applying heat or ice, eating soft foods and a short course of anti-inflammatory drugs. Others may prescribe mouth guards to prevent clenching and grinding teeth at night, yet there is no gold standard for treatment. According to Dr. Stohler, "The best we can do is provide a caring, compassionate environment and take case by case to treat each patient individually."

For more information contact the TMJ Association (www.tmj.org).

The Society for Women's Health Research is the nation's only not-for-profit organization whose sole mission is to improve the health of women through research. Founded in 1990, the Society brought to national attention the need for the appropriate inclusion of women in major medical research studies and the resulting need for more information about conditions affecting women. The Society advocates increased funding for research on women's health, encourages the study of sex differences that may affect the prevention, diagnosis and treatment of disease, and promotes the inclusion of women in medical research studies. Dr. Donnica Moore has been a member of the Society since 1990 and is a past member of its Board of Directors.

Created: 2/20/2003  -  Jennifer Wider, M.D.
Reviewed: 2/21/2003  -  Donnica Moore, M.D.