Development of objective diagnostic system of tooth mobility

牙齿运动检查是评估牙周组织状况的重要方法。虽然从生活质量的角度来看，种植牙治疗在日本老年人中非常有价值，但目前还没有建立一种诊断种植牙的方法。本研究旨在开发牙齿移动的客观诊断系统。作者已研制出牙齿移动自动诊断系统，并已用于临床实验。然而，由于需要一台个人计算机来进行数据采样和分析，它相当大。研制的临床用牙齿移动度测试仪（T-M测试仪）由测量探头和系统放大器组成，具有尺寸便携、测量快速等特点。对齿面施加单频振动，检测到加速度响应。该测量值是最近提出的牙齿移动指数，称为移动指数（MI）。在三年的研究期间，对临床实验用T-M测试仪I和II进行了试验，并对其进行了临床评价。在对小细节进行修改后，完成了牙齿移动的客观诊断系统。测量探头的总长度为120mm，探头的尖端为弯曲型压电陶瓷内直径为10mm的圆柱形。探头手柄弯曲成15度角，便于插入口中。测量频率为400hz。虽然探针的末端插入一次性覆盖物，但该探针和测试仪的临床适用性通过人工牙模型和人牙来证实。测量变异系数在几个百分点以内。

Tooth movement examination is important in estimating the condition of the periodontium. Though dental implant treatments in the aged of Japan are very valuable from the viewpoints of quality of life, a diagnostic method for implantation is still not established. This study aims a development of objective diagnostic system of tooth mobility. The authors have already developed the automatic diagnosis system of tooth mobility and have used it in clinical experiments. It is, however, fairly large because of the requirement for a personal computer for data sampling and analysis. The developed tooth mobility tester (T-M tester) for clinical use is composed of a measurement probe and system amplifier and is characterized by its portable size and rapid measurement. A single-frequency vibration is applied to the tooth surface, and an acceleration response is detected. The measured value is newly proposed as the index of tooth mobility, termed the mobility index (MI).For three years of the research period, the T-M tester I and II for clinical experiments have made on a trial basis and the clinical evaluation of them is made. After the modification for minor details, the objective diagnostic system of tooth mobility has been completed. The measuring probe has an overall length of 120 mm and the pointed end of the probe is a cylindrical shape of 10 mm in diameter within bender-type piezoelectric ceramics. The handle of probe is bent at an angle of 15 degree, so as to be easily inserted in the mouth. The measurement frequency is 400 Hz. The clinical applicability this probe and tester is confirmed using an artificial tooth model and human teeth, though the end of probe is inserted into a disposable covering. The coefficient of measurement variation is within several %.