PERIODONTAL TISSUE ANALYSIS WITH MECHANICAL IMPEDANCE MEASUREMENT

本研究的目的是建立一个能够反映正畸牙齿移动过程中牙周组织动态变化的生物学指标，而不对牙周组织造成任何损伤。对于这项研究，我们选择了一个机械阻抗测量设备，我们做了几个改进，以调整它为我们的目的。然后，利用该装置进行了一些临床观察，以了解牙齿支持结构，主要是牙周组织的情况。研究对象如下：1.使用正常萌出的完整牙齿，该测量装置测量的再现性。2.正常萌出完整牙的粘弹性在一天内和一天内的变化.研究了正畸牙齿移动过程中粘弹性能的变化与牙齿移动量的关系，并对该装置进行了重复性测试，结果表明该装置具有良好的重复性。的变异系数 ...更多信息 测量值小于10%（2.7%-8.2%）。完整牙齿一天内的粘弹性变化，每隔1小时测量9次，与该装置的再现性相比，显示出稍大的变化（7.2%-12.0%）。在几天内的粘弹性性质的变化进行了测量，每周两次，为期四周。在正畸牙齿移动过程中，每颗牙齿，甚至临床正常的犬齿，在前四周内，对牙齿移动量和粘弹性变化的组织反应不同。根据Reitan的观点，正畸牙齿移动的早期可分为两个阶段。在初始阶段，牙齿通过牙周纤维的压缩而移动，在第二阶段，牙齿通过骨吸收而移动。在这两个时期之间，有一个玻璃化时期，牙齿暂时停止运动。在本研究中，在正畸牙齿移动期间，粘弹性值的暂时增加与牙齿移动的暂时停止期同时发生，本课题的研究结果表明，牙周组织粘弹性的变化可以反映牙周组织的状况，组织.提示该方法有可能成为临床上判断正畸牙移动过程中牙周组织状况的有效指标。少

The purpose of this project is to develop an index that indicates the dynamic and biological periodontal tissue changes during the orthodontic tooth movement without any invasion to the tissue. For this study, we chose a mechanical impedance measuring device and we made several improvements to adjust it for our purpose. Then, some clinical observations were carried out with this device as the means to know the conditions of tooth supporting structures, mainly the periodontal tissue. The following subjects were investigated.1. The reproducibility of the measurements of this measuring device, using normally erupted intact tooth.2. The change of the viscoelastic property of the normally erupted intact tooth during a day and during days.3. The relationship between the change of the viscoelastic property and the amount of the tooth movement during the orthodontic tooth movement.The reproducibility of the measurements of this device showed a good result. The coefficients of variations of the … More values of measurements were less than 10% (2.7%-8.2%). The viscoelastic property changes during a day of the intact tooth, which were measured nine times at one hour intervals showed slightly larger variations (7.2%-12.0%) comparing to the reproducibility of this device. The viscoelastic property changes during days were measured twice a week for four weeks. The coefficients of variations of the change during days values showed largest values (8.0%-17.1%) among these three.During orthodontic tooth movement, each tooth, even clinically normal canines, showed the different tissue reactions in the first four weeks, about the amount of the tooth movement and the viscoelastic property change. According to Reitan, The early stage of the orthodontic tooth movement could be divided into two periods. In the initial period, a tooth is moved by the compression of the periodontal fibers and in the secondary period, a tooth is moved by the bone resorption. Between these two periods, there is a hyalinized period in which the tooth stops its movement temporarily. In this investigation, during orthodontic tooth movement, temporary increment of the viscoelastic property values coincidentally occurred with the temporary stop period of the tooth movement, and the relationship between the viscoelastic property changes and the tooth movement was strongly suggested.The results of this project suggest that the investigations about the viscoelastic property changes of the periodontal tissue could indicate the conditions of the periodontal tissue. It also suggested that this method had the possibility to be the clinically efficient index to determine the periodontal tissue conditions during the orthodontic tooth movement. Less