A system for simultaneous signals acquisition of EMG activity, bite force, and muscle pain, reveals the rotation of synergistic activity in the human jaw elevator muscles

Aim of the present study was to describe a multipurpose system to be used in oral physiology research, which has been developed in order to simultaneously acquire multiple signals from the masticatory muscles (i.e. bite force, EMG activity, and muscle pain). A preliminary study was carried out to test the performance of this system in ten subjects. We investigated the effect of prolonged isometric jaw clenching at different force levels on the EMG activity of paired masseter and temporalis muscles, while monitoring bite force and local pain perceived in the muscle investigated.