Hormonal Cycles in Women: Effects on TMD Pain & Symptoms

Temporomandibular disorders (TMD) are a group of painful conditions involving the muscles of mastication and the temporomandibular joint. These pain problems are about twice as common in women as in men in the community, and prevalence peaks during the reproductive years. The etiology of TMD pain is unknown, but psychological stress, depression and the presence of other somatic complaints have been shown to influence the course of these disorders. Prior research suggests that female reproductive hormones may also influence TMD pain. Specifically, normally cycling women with TMD experience rising levels of TMD pain pre-menstrually during a time of precipitous drop in estrogen and show peak TMD pain during menses. Interestingly, a secondary peak of TMD pain occurs at about the time of ovulation, another phase corresponding to rapid estrogen change. These data demonstrate a systematic relationship between levels of TMD pain and phases of the menstrual cycle. The proposed clinical trial will manipulate the behavioral and hormonal factors that are hypothesized to influence TMD pain, comparing the effects of:

• a continuous oral contraceptive intervention designed to suppress menses and stabilize the hormonal environment;
• a self-management intervention focused on and timed to the chronobiology of TMD symptoms across the menstrual cycle; and
• a usual self-management intervention not timed to biological events. The aims of this clinical trial are to shed light on the mechanisms underlying the cyclic nature of TMD pain and symptoms in women, as well as to determine which treatment modality results in the greatest improvement in TMD pain and symptoms.