Yugami K
1st Department of Prosthodontics, Tokyo Medical and Dental University, Japan.
Kokubyo Gakkai Zasshi. 1996 Mar;63(1):31-41. doi: 10.5357/koubyou.63.31.
In order to evaluate the relationship between the mandibular position and the muscle activity during bruxism, an originally-designed device for detecting tooth contacts in eccentric jaw positions in addition to the intercuspal position was applied to 7 subjects and electromyography was carried out stimultaneously. Nocturnal bruxing patterns such as lateral grinding, clenching in the intercuspal position or eccentric jaw position were clearly distinguished by using this system. In one of 3 subjects who were not aware of bruxism, both the duration and the frequency of the muscle activity were significantly higher than those of other subjects. This suggests that some persons with bruxism who are unaware of it actually grind or clench their teeth during sleep. Tooth contacts during sleep were classified into 6 patterns according to jaw position. In the IP pattern, both regular and irregular EMG patterns were observed without any lateral movement of the mandible. Furthermore, each subject had the mandibular position on the preference side during tooth contacts and the EMG activity of the anterior temporal muscle on the preference side during the IP pattern was higher than that on the opposite side. This system enabled detailed evaluation of bruxism.
为了评估磨牙症期间下颌位置与肌肉活动之间的关系，一种最初设计的用于检测除牙尖交错位之外的下颌偏位时牙齿接触的装置被应用于7名受试者，并同时进行肌电图检查。通过使用该系统，可以清楚地区分夜间磨牙模式，如侧向研磨、牙尖交错位或下颌偏位时的紧咬。在3名未意识到磨牙症的受试者中，有1名受试者的肌肉活动持续时间和频率均显著高于其他受试者。这表明，一些未意识到自己有磨牙症的人实际上在睡眠期间会磨牙或紧咬牙。根据下颌位置，睡眠期间的牙齿接触被分为6种模式。在牙尖交错位模式中，观察到规则和不规则的肌电图模式，下颌无任何侧向移动。此外，每个受试者在牙齿接触时有偏好侧的下颌位置，并且在牙尖交错位模式期间，偏好侧颞肌前部的肌电图活动高于对侧。该系统能够对磨牙症进行详细评估。
