人咬肌的肌构筑学研究

对10侧人咬肌的肌构筑学研究表明，咬肌浅部为多羽肌，内部有3－5个与肌表面平行排列的腱板，肌纤维从浅深两面附着于腱板上，深部为带状肌，肌纤维并行排列几乎垂直下行，咬肌浅部明显重于深部，约为深部的2．5倍，生理横切面积约为深部的2倍，但生理横切面积／肌重比率却明显小于深部，浅，深两部各项构筑指数在左，右侧无显性差异，以上结果提示，咬肌浅，深两部均属于力量型肌，咬肌浅部在咀嗳活动及保持下颌位置中起主导作用，深部对下颌姿势位的维持和稳定颞下颌关节的正常位置是必不可少的，本研究结果为进一步研究咬肌的肌生理和肌运动学提供可靠的资料。

Investigation of Muscle Architecture on Human Masseter Muscle

The architectural features of the masseter muscle were studied in five cadavers. The re-sults showed that the superficial portion of the masseter was a multipennate muscle, with three to five aponeurosis arranged in parallel with the surface of the muscle,to which the fibers attached' The deep portion is straplike,its fibers ran vertically downward' The weight of the superficial portion was about 2. 5 folds of that of the deep portion. The physiological cross-sectional area of the former was about 2.0 times of that of the latter,but the ratio of cross-sectional area/muscle weight of the superficial portion was significantly less than that of the deep portion. There were not any statistical differences for the architectural indices of the superficial and deep portions between the left and right sides of the masseter muscles.These results suggest that both the superficial and deep portions were designed for force pro-duction,of which the superficial portion played a ma jor role in chewing activity and maintin-ing mandibular position,and the deep portion was necessary in keeping the mandibular postu-ral position and stabilizing the liormal position of temporomandibular joint. These results provide the reliable data for studing myophysiology and myoktnesiology in a deepgoing way.