Study for developing new caries removal device with air-abrasive technique.

结果表明，以桃仁壳为原料，在3 kgf/cm ^2的气压下，用100μm左右的颗粒进行空气研磨，可选择性地去除龋坏牙本质。（科学研究资助金（B））然而，完全去除龋齿组织需要很长时间。为了提高龋齿去除的功效，检查了空气压力和/或颗粒尺寸的几个条件。虽然当提供较大的气压和/或使用大颗粒时，龋组织的去除时间缩短，但在这些条件下，患者在临床使用中感到疼痛。通常空气磨损采用干式技术（颗粒被压缩空气加速），我们尝试使用湿式技术（颗粒被压缩空气和水一起加速）。虽然，众所周知，干式技术的切削效果上级湿式技术，但在本研究中，阐明了湿式技术的去龋效果上级干式技术。认为干燥龋坏的牙本质在使用干燥技术时变硬。湿法技术具有额外的优点，即减少分散的颗粒，减少切割表面的热量，并减少患者的痛苦。结果表明，桃仁粉湿空气研磨技术在临床上是可行的。经证实，树脂粘结系统的粘接强度之间的无显着差异，使用湿空气磨损技术与桃仁粉，并使用传统的旋转切割设备的去龋牙表面。从现在起，将开始改善临床操作。

It was revealed that air abrasive technique with particle (size about 100μm) which was made of the peach seed shell selectively removed caries dentin under air pressure of about 3kgf/cm^2. (GRANT-IN-AID FOR SCIENTIFIC RESERCH (B)) However, it takes a long time to remove caries tissue completely. To improve the efficacy of caries removal, several conditions of air pressure and/or particle size were examined. Though the removal time of caries tissue became short when larger air pressure was supplied and/or large particle was used, under those conditions patients feel pain in clinical use. Usually air abrasion uses dry technique (particles are accelerated by compressed air), we tried to use wet technique (particles are accelerated by compressed air together with water). Though, it is well known that the cutting effect of dry technique is superior to that of wet technique, in this study it was elucidated that caries removal efficacy of wet technique was superior to that of dry technique. It is considered that dried carious dentin became hard when dry technique was used. The wet technique has additional advantages, namely reducing scattered particles reducing the heat of cutting surface and reducing patients' pain. It was ascertained that wet air abrasion technique with peach seed powder is clinically useful in this study. It was confirmed that there was no significant difference between adhesion strength of resin bonding system to the surface of caries removed tooth using wet air abrasion technique with peach seed powder and that of using the conventional rotary cutting device. From now the improvement of the clinical operation will be started.