Prevalence of temporomandibular disorders (TMD) in children based on physical signs.

Temporomandibular disorders (TMD) are related to the function and integrity of the masticatory system with restricted jaw movement and/or joint clicking or crepitus, for example, dominating the clinical signs of these disorders. The prevalence of TMD signs was examined in non-patient children ages six to twelve (1994 n = 185, 1995 n = 237) by four examiners using standardized techniques. Of significance was the finding that 7.3 percent of the 1994 children had audible joint sounds, while the 1995 examination reported 3 percent. Statistically significant relationships (p < 0.05) between the ages of the subjects and measurements of overbite (p < 0.0001), overjet (p < 0.01), and clicking (p < 0.005) were calculated from the 1994 data, while significant correlations for overbite (p < 0.001) and overjet (p < 0.01), but not clicking were found in the 1995 examination. One study of four- to six-year-old nonpatients reported a higher occurrence of joint sounds (48 percent). This disparity indicates a possible need for standardization of examination techniques specifically targeting joint sounds and their role in TM disorders.