Abstract
Purpose: The purpose of this study was to investigate the effect of loss of posterior occlusal support on the stabilization of posture stance disturbed by electrical stimulation.
Methods: Experiments were performed on 15 young healthy adults (aged 26.3±3.1; mean ± SD). The subjects stood on a force plate with eyes open and in the upright position. The common peroneal nerve of the right leg was stimulated randomly by supramaximal percutaneous electrical stimulation once every 8 to 10 s to contract their peroneus longus and tibialis anterior muscles involuntarily. We analyzed the total length, anterior/posterior and lateral amplitude of body sway under the following three occlusal conditions: mandibular rest position (Control), maximum voluntary teeth clenching with splint covering only anterior teeth (AntSP-CL), and maximum voluntary teeth clenching (CL).
Results: The total length (p<0.01) and anterior/posterior amplitude of body sway (p<0.05) under the CL condition were significantly lower than those under the Control condition. The total length of body sway and anterior/posterior amplitude under the AntSP-CL condition did not show statistical differences compared with the Control and CL (one-way ANOVA, Bonferroni correction method).
Conclusions: It is suggested that occlusal supports of molar teeth would contribute to postural adaptation caused by teeth clenching to a novel environment. Accordingly, we consider that they would play an important role in not only masticatory function but also motor function.
