Schindler Hans J, Rues Stefan, Türp Jens C, Schweizerhof Karl, Lenz Jürgen
Research Group Biomechanics, Faculty for Mathematics, University of Karlsruhe, Germany.
Eur J Oral Sci. 2005 Dec;113(6):469-78. doi: 10.1111/j.1600-0722.2005.00249.x.
In 10 normal subjects, the electromyographic (EMG) activities of the masseter, anterior and posterior temporalis, medial pterygoid, inferior lateral pterygoid, as well as the anterior digastric, were bilaterally recorded during clenching with various resulting force vectors. The intraoral force transfer was achieved with a three-component force transducer. The direction and magnitude of the force vectors were controlled by visual feedback. The goal of the study was to investigate how various clenching directions at constant magnitude of force influence the EMG activity in the masticatory muscles during gradual increase of the horizontal force component. Depending on the force direction and the individual muscle, an increase or decrease of activity was observed during clenching with increasing horizontal force components at constant magnitude of force. The inferior lateral pterygoid exhibited the highest activation (about 80% of maximal voluntary clenching) of all masticatory muscles. The medial pterygoid showed the greatest range of variation in activation behavior, and it was the most active muscle in relation to all clenching directions. In conclusion, the results show that with growing horizontal force components at constant magnitude of force, all muscles demonstrated an increase or decrease of activity in several clenching directions.
在10名正常受试者中，在以各种合力矢量进行紧咬时，双侧记录了咬肌、颞肌前束和后束、翼内肌、翼外肌下束以及二腹肌前腹的肌电图（EMG）活动。使用三分量力传感器实现口内力传递。力矢量的方向和大小通过视觉反馈进行控制。本研究的目的是调查在力的大小恒定的情况下，各种紧咬方向如何在水平力分量逐渐增加的过程中影响咀嚼肌的肌电图活动。根据力的方向和个体肌肉的不同，在力的大小恒定且水平力分量增加的紧咬过程中，观察到活动增加或减少。翼外肌下束在所有咀嚼肌中表现出最高的激活程度（约为最大自主紧咬的80%）。翼内肌在激活行为上表现出最大的变化范围，并且在所有紧咬方向上都是最活跃的肌肉。总之，结果表明，在力的大小恒定的情况下，随着水平力分量的增加，所有肌肉在几个紧咬方向上均表现出活动增加或减少。
