A comparison of the signs of temporomandibular joint dysfunction and occlusal discrepancies in a symptom-free population of men and women.

To date, there has been no conclusive explanation for the predominance of female patients with temporomandibular joint (TMJ) dysfunction. The purpose of this study was to survey a normal population without symptoms for the presence of certain putative signs of TMJ dysfunction in association with certain signs of occlusal discrepancy and to determine the presence of any gender variation. The subjects (217 men and 217 women) were examined for the presence of three putative signs of TMJ dysfunction: limited mandibular opening (under 37 mm), deviation on opening, and joint sounds. The subjects were also examined for the presence of four signs of occlusal discrepancy: an anterior slide from centric relation (CR) to centric occlusion (CO), lateral slide from CR to CO, nonworking occlusal contacts, and working disclusive contacts distal to the canines. CR is the mandibular position at which the condyles are in their most superior position on the posterior aspect of the articular tubercles. CO is the mandibular position at which the mandibular and maxillary teeth are in maximum intercuspation. There were no significant differences in the prevalence of the putative signs of TMJ dysfunction and occlusal discrepancy between men and women. It was concluded that factors other than the presence of these signs of TMJ dysfunction and occlusal discrepancy are responsible for the high predominance of female patients with TMJ dysfunction.