Abstract
The purpose of this study was to analyze the masseter EMG activity pattern affected by alteration of tooth-tapping frequency and biting force. Ten subjects were asked to do tapping synchronized with a auditory signal at 0.5, 1, 2, 3 or 5 Hz. They were also required to do tapping with three different biting force. The EMG was analyzed on silent period (SP), burst before SP (B1) and burst after SP (B2). The results was summarized as follows:
1. The duration of B1 was not affected by change of tapping frequency and biting force, and it was always constant.
2. The durations of B2 and SP were strongly affected by change of tapping frequency, and they were decreased with an increase of tapping frequency.
3. The amplitudes of B1 and B2 were strongly affected by change of biting force, and they were increased with an increase of biting force.
These results showed that each component of masseter EMG was selectively affected by the tapping frequency and/or biting force.
