Fundamental and clinical study of masticatory system in Osseointegrated implants

我们确定骨结合固定装置的活动性特征对于规划各种类型的上部结构可能非常重要。本实验研究了牙周膜机械感受器与天然牙不同结构的骨结合固位体在2000 g载荷下的唇、舌向移动度，上测点为37-114 <micro>m，下测点为26-71 <micro>m，这些数值均小于下颌双尖牙活动度的数值。夹具的移动性与载荷成正比，直到2000 g，并且在去除载荷后没有观察到蠕变。在骨结构的影响下，每个固定器的旋转中心表现出一定的特点，特别是边缘骨和固定器顶端周围骨的性质差异程度，并研究了固定器周围组织的触觉敏感性。在静态载荷下，触觉阈值大于100 g，动态载荷下触觉阈值大于35 g，均明显高于天然牙。探讨了无支座时消除隔膜影响的阈值。两种情况之间无显著差异。我们认为基牙周围膜的机械感受器在如此小的活动度下可能不起作用。

It may be very important that we determine mobility characteristics of osseointegrated fixtures for the planning various types of superstructure. It would be useful to investigate the mechanisms of the masticatory system in order to elucidate the tactile sensitivity of osseointegrated fixture which has a different structure from the natural tooth with mechanoreceptors in the periodontal ligament.The fixture showed the following mobility values for labial and lingual directions under a load of 2000g: 37-114 <micro> m at upper measuring point and 26-71 <micro> m at lower m.p., These values were smaller than those seen with the mobility of bicuspid in mandible. The mobility of fixture was in direct proportion to loads up to 2000g and no creep was observed after removal of loads. The rotation center in each fixture showed peculiarities under the influence of the bone structure, especially the degree of difference between properties of the marginal bone and the bone surrounding the apex of fixture.And tactile sensitivity of the tissue surrounding fixture was investigated. The tactile thresholds were more than 100g under static loading and more than 35g under dynamic one, these values were remarkably higher than natural tooth. The threshold of it without abutment to elininate the influence of membrane was investigated. There was no significant difference between two conditions. We suggested that the mechanoreceptor in membrane surrounding abutment might not work under such small amount of mobility.