| Abstract: | This article describes a system that allows for simultaneous analysis of subjects' mandibular movements and electromyographic activity during chewing. The authors examined clockwise and counterclockwise movements separately, using the following parameters for the opening and closing strokes at 20 different degrees of jaw separation: 1. Number of times the movement occurred. 2. Mean displacement values. 3. Actual velocity. 4. Velocity values on the three coordinates X, Y, and Z. A plotter was used for a graphic analysis of the movements. The system recorded electromyographic activity from both masseters with a two-channel electromyograph. (However, the system can record up to eight channels at once.) After the data was collected, the mean electrical activity for each degree of jaw separation during opening and closing was calculated. The system used for this study seems to be a reliable and comprehensive means of assessing masticatory activity in function and dysfunction. |
