Archives of oral biology vol:30 issue:2 pages:177-80
In mandibular joint-symptom-free subjects, post-stimulus EMG complexes (PSEC) were derived by standardized mechanical stimulation of an upper central incisor during clenching at a constant level of 5 per cent of maximal masseteric EMG activity. Seventy-two sweeps per subject were processed by means of a computer program, and different morphologies of the PSEC were seen. There appears to be no correlation with the Helkimo-index as a whole or its specific components. There is a strong correlation between tooth-grinding habits and the occurrence of a single inhibitory period. Patients with myofascial pain dysfunction consistently had a single inhibitory wave. When there was one affected side, the end latency of the second inhibitory wave was significantly shorter.