Study of Relaxation of the Muscles of the Chewing Complex after the Functional Load

Surface electromyography of spontaneous muscle activity is the most common method for assessing the functional state of the muscle complex. The surface electromyogram signal has a noise-like appearance with a signal amplitude changing over time. The change in background activity and the probability of high-amplitude amplitude spikes, a short-term significant increase in the electromyogram amplitude, were studied. A change in background activity can be associated with both technical factors, such as changes in the resistance of the skin-electrode contact, and directly with the state of the muscle complex and the inability of the muscles to relax instantly. High-amplitude spikes can also appear due to many factors – electrode displacement, recording of extraneous muscle contractions, muscle spasms, etc. Synchronous electromyograms of the temporal and masseter muscles were analyzed. The study of background activity and the presence of high-amplitude spikes showed a difference in the rate of muscle relaxation before and after the functional load test, as well as a difference in the rate of relaxation between the temporal and masseter muscles.