TMD-like symptoms elicited by voluntary low-level jaw clenching. 10 These previous studies provide highly mixed support for a possible etiologic or maintenance role for estrogen in the pathogenesis of TMD. We undertook a study to further elucidate the relationship between exogenous estro- gen use and TMD. We confirmed current Background. Studies of historical data suggest a link between exog- enous estrogen use and referral for treatment for temporomandibular dis- orders, or TMDs. The purpose of the authors’ study was to determine the association between exogenous estrogen use and signs and symptoms of TMD assessed by direct physical examination in a randomly selected community sample of primarily postmenopausal women. Methods. A calibrated clinical examiner examined a stratified random sample of 510 women aged 37 to 82 years using the Cra- niomandibular Index, or CMI. All medica- tions that subjects were taking at the time of the examination were identified by inter- view and examination of subjects’ medica- tion containers on two occasions. One hun- dred seventy-four subjects were taking medications containing estrogen, and 336 were taking no such medications. Results. The muscle and joint signs and symptoms of women taking and not taking estrogen were not significantly different after the authors controlled for sociocul- tural, demographic and health care utiliza- tion variables. Estrogen use also failed to distinguish women receiving relatively high and low scores on the CMI. Conclusion. Estrogen replacement therapy does not place women at increased risk of developing TMDs. Clinical Implications. Clinicians need not be concerned that patients taking oral contraceptives or replacement estrogens are at increased risk of developing TMDs. Is use of exogenous estrogen associated with temporomandibular signs and symptoms? JOHN P. HATCH, Ph.D.; JOHN D. RUGH, Ph.D.; SHIRO SAKAI, D.D.S., M.S.; MICHELE J. SAUNDERS, D.M.D., M.S., M.P.H. T he differential prevalence of temporomandib- ular disorders, or TMDs, in men and women has long puzzled dental clinicians and re- searchers. Population-based studies show the prevalence of TMD to be from about two to five times higher in women than in men in community samples. 1-3 The differen- tial prevalence is even greater in clin- ical samples. 2 No plausible explanation for the higher prevalence of TMD in women has been proposed, but it seems reason- able to ask whether the sex hormones may play some role in etiology or main- tenance of the condition. For instance, variations in sex hormone levels associ- ated with the menstrual cycle may mod- ulate pain perception. 4-7 Also, prescrip- tion of exogenous estrogen in the form of estrogen replacement in menopause or oral contraceptives during reproduc- tive years may increase the risk of being referred for TMD care. 8 Exoge- nous estrogen in the form of oral contra- ceptives does not affect mean pain intensity ratings in regularly ovulating patients with TMD, but it might affect the pattern or variability of pain rat- ings. 9 In addition, use of oral contraceptives in healthy ovulating women does not affect the development of ABSTRACT JADA, Vol. 132, March 2001 319 There appears to be no association between estrogen use and the component signs and symptoms of the temporo- mandibular disorder syndrome in a randomly selected community sample. J A D A C O N T I N U I N G E D U C A T I O N ✷ ✷ ® CLINICAL P R A C T I C E J A D A C O N T I N U I N G E D U C A T I O N ✷ ✷ ® A R T I C L E 2 Copyright ©1998-2001 American Dental Association. All rights reserved.