Electromyographic silent periods and jaw motion parameters: quantitative measures of temporomandibular joint dysfunction.

The purpose of this research was to compare, in the subjects, the duration of the EMG silent period with jaw motion error. The results indicate that both jaw motion error and silent period duration are large in patients with TMJ-muscle-pain dysfunction, both are small in normal subjects, and both are small in successfully treated patients. There is a statistically significant correlation (r=0.91; P less than 0.01) between the two diagnostic parameters of TMJ-muscle-pain dysfunction.