Miralles R, Valenzuela S, Ramirez P, Santander H, Palazzi C, Ormeño G, Zúñiga C
Oral Physiology Laboratory, Faculty of Medicine, University of Chile, Santiago, Chile.
Cranio. 1998 Jul;16(3):168-84. doi: 10.1080/08869634.1998.11746055.
This study was conducted in order to determine the input visual effect on electromyographic (EMG) activity of the sternocleidomastoid and masseter muscles in the supine and lateral decubitus positions. The study was performed on 22 patients with myogenic cranio-cervical-mandibular dysfunction (CMD) and 18 healthy subjects. EMG activity at rest and during swallowing of saliva and maximal voluntary clenching was recorded in the supine and lateral decubitus positions in the following conditions: 1. with eyes open; and 2. with eyes closed after 5 minutes in a dark room. A significant decrease of EMG activity at rest with closed eyes in both groups was observed in the sternocleidomastoid (lateral decubitus position) and in the masseter muscle (supine position). During swallowing of saliva a significant decrease of EMG activity with closed eyes was observed only in the sternocleidomastoid muscle (lateral decubitus position) in healthy subjects. During maximal voluntary clenching any significant differences were observed upon variation in the visual input. The significant change in EMG activity, mainly observed at rest, suggests that the visual input effect is weak. The absence of a significant change in EMG activity during maximal voluntary clenching upon variation in the visual input could be clinically relevant in patients with myogenic CMD who habitually brux.
本研究旨在确定仰卧位和侧卧位时视觉输入对胸锁乳突肌和咬肌肌电图（EMG）活动的影响。该研究对22例肌源性颅颈下颌功能障碍（CMD）患者和18名健康受试者进行。在以下条件下，于仰卧位和侧卧位记录静息状态、吞咽唾液以及最大自主紧咬时的EMG活动：1. 睁眼；2. 在暗室中5分钟后闭眼。在两组中均观察到，胸锁乳突肌（侧卧位）和咬肌（仰卧位）在闭眼静息时EMG活动显著降低。在健康受试者中，仅在侧卧位的胸锁乳突肌吞咽唾液时观察到闭眼时EMG活动显著降低。在最大自主紧咬时，未观察到视觉输入变化产生任何显著差异。EMG活动的显著变化主要在静息时观察到，这表明视觉输入影响较弱。对于习惯性磨牙的肌源性CMD患者，视觉输入变化时最大自主紧咬期间EMG活动无显著变化可能具有临床意义。
