Department of Prosthodontics, Dental School, University of Heidelberg, Heidelberg Research Group Biomechanics, Institute for Mechanics, Karlsruhe Institute of Technology, Karlsruhe, Germany.
J Oral Rehabil. 2011 Oct;38(10):729-36. doi: 10.1111/j.1365-2842.2011.02211.x. Epub 2011 Mar 9.
Alterations of body sway caused by isometric contractions of the jaw muscles have been reported previously. The objective of this study was to test if motor tasks of the masticatory system with different control demands affect body posture differently during quiet stance. Position and sway displacements of the center of foot pressure (COP) were measured for 20 healthy subjects who either kept the mandible at rest or performed unilateral and bilateral maximum voluntary teeth clenching, feedback-controlled biting tasks at submaximum bite forces, or unilateral chewing. Two weeks later the measurements were repeated. Compared with quiet stance, the COP results revealed significant changes during the feedback-controlled biting tasks. Robust sway reduction and anterior displacement of the COP were observed under these conditions. Body oscillations were not significantly affected by maximum bites or by unilateral chewing. For most of the variables investigated there were no significant differences between unilateral and bilateral biting. Robust sway reduction during feedback-controlled biting tasks in healthy subjects involved a stiffening phenomenon that was attributed to the common physiological repertoire of posture control, and might optimize the stability of posture under these conditions.
先前已有报道称，颌肌肉等长收缩会导致身体摇晃发生改变。本研究的目的是测试咀嚼系统的不同运动任务在安静站立时是否会以不同的方式影响身体姿势。为 20 名健康受试者测量了足底压力中心（COP）的位置和晃动位移，这些受试者或让下颌保持静止，或进行单侧和双侧最大自主牙齿咬紧、次最大咬合力反馈控制咬合任务，或单侧咀嚼。两周后重复测量。与安静站立相比，在反馈控制咬合任务期间，COP 的结果显示出明显的变化。在这些条件下，观察到稳定的晃动减少和 COP 的前向位移。最大咬合或单侧咀嚼对身体摆动没有明显影响。对于大多数被调查的变量，单侧和双侧咬合之间没有显著差异。在健康受试者中，反馈控制咬合任务期间的稳定晃动减少涉及到一种僵硬现象，这归因于姿势控制的共同生理储备，并可能在这些条件下优化姿势的稳定性。
