Shi C S, Wang H Y
Department of Oral Physiology, Dental Hospital, Fourth Military Medical College, Shaanxi, People's Republic of China.
J Oral Rehabil. 1989 Mar;16(2):155-61. doi: 10.1111/j.1365-2842.1989.tb01328.x.
Electromyograms (EMGs) of the temporal and masseter muscles in sixty patients with temporomandibular joint disturbance syndrome (TMJDS) and thirty controls were recorded and integrated on-line in the postural position and during maximum clenching, before and after occlusal splint therapy. Contrasting with the controls, the myoelectrical activity of the patients was higher in the postural position and lower during maximum clenching, whilst the former in percentage terms increased when compared to the latter. After treatment, the EMG indexes in some patients returned partially, and in others completely, to a normal level. Tenderness in the mandibular elevators, deviated opening and organic change in the TMJ increased the postural myoelectrical activity, in percentage terms, against that of maximum clenching. The myoelectrical activity of the mandibular elevators in the postural position and during maximum clenching was smaller in patients with the occlusal splint than in those without. The results show that the mandibular elevators in the patients with TMJDS were hyperactive and tense, and that the occlusal splint was useful for treating such dysfunction.
