title: Sex differences in masticatory muscle pain after chewing.
abstract: Neither the etiology of muscle-related temporomandibular disorders (TMD) nor the reason for the disproportionate number of women suffering from these disorders is well-established. We tested the hypothesis that physiologically relevant exercise (i.e., chewing bubble gum for 6 min) increases masticatory muscle pain in patients, but not in asymptomatic control subjects, and that female patients experience a significantly greater increase than males. Chewing increased pain in both female and male patients and, unexpectedly, also in female control subjects. One hour after chewing, the pain remained above pre-test levels for female patients but not for the other groups. Thus, sex differences in chewing-induced pain were found in control subjects but not as hypothesized in patients. Because chewing-induced masticatory muscle pain was significantly greater in female control subjects than in males, and persisted longer in female patients than in males, these results suggest greater susceptibility in women.
authors.affiliation: Center for Orofacial Pain, NIH Pain Center, Department of Oral and Maxillofacial Surgery-Box 0440, University of California-San Francisco, San Francisco, CA 94143-0440, USA.
authors.forename: H
authors.initials: H
authors.lastname: Karibe
authors.forename: G
authors.initials: G
authors.lastname: Goddard
authors.forename: R W
authors.initials: RW
authors.lastname: Gear
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D016022:Case-Control Studies; D004198:Disease Susceptibility; D005157:Facial Pain / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008406:Masseter Muscle / Q000503:physiopathology*; D008409:Mastication; D010147:Pain Measurement; D016059:Range of Motion, Articular; D012727:Sex Characteristics; D013706:Temporomandibular Joint Dysfunction Syndrome / Q000503:physiopathology*