A NEW METHOD FOR RECORDING MANDIBULAR POSITION DURING NOCTURNAL BRUXISM

Experimental equipment for recording mandibular excursive position dur ing nocturnal bruxism has been devised. The equipment consists of chro mium-cobalt alloy cast frameworks for each upper and lower dental arch and two pairs of tiny magnetic sensors and magnets, capable of electr omyographic (EMG) recordings of the bilateral masseter muscles and sim ultaneously recording mandibular position. The two subjects tested wer e confirmed to be bruxing during sleeping. Although EMG records for th e two subjects showed a common EMG pattern as a bruxer, the sensor rec ords revealed that one subject was a bilateral bruxer and the other br uxed almost unilaterally. The present study demonstrated that this new ly devised equipment is practical for studying mandibular position dur ing nocturnal bruxism.