Studies on Prevention of Contamination of Air-turbine Handpiece.

近年来，各种防污染装置相继问世。当空气透平脚踏开关松开时，防污染装置(PS)立即向送风管、排气管和切屑送风管提供少量压缩空气。它保持头部的正压，并抑制污染物的渗透。防污染空气涡轮机头(CH)在钻头侧主轴上有一个小圆盘，在空气涡轮机头外壳周围有一个浅槽。该盘产生的离心力和迷宫机构一起抑制污染物侵入内室和管路系统。本研究的目的是临床调查空气涡轮手机的细菌污染，评估两种对策(PS，CH)的效果，并评价新设计的“空气涡轮手机吸气净化器”的效果。新型去污机的特点是：1.手机外表面可用80%乙醇消毒；2.手机运行180秒后，污染物排入吸口，使用PS&CH后，内部细菌污染降至不使用时的0.2%以下。通过使用新设计的去污器，180个传感器就可以将这些细菌从手机上完全清除出来。在使用PS&CH时，送风管、排气管、芯片送风管和给水管均未检出细菌污染，说明使用PS&CH新设计的“空气涡轮手机吸气净化器”可以有效地防止空气涡轮手机的污染。

Recently, various anti-contamination devices have been developed. The anti-contamination device (PS) supplies a small amount of compressed air into air feed tube, exhaust tube and chip air feed tube at once when the air-turbine foot switch is released. It keeps a positive pressure in the head and infiltration of contaminant is inhibited. The anti-contamination air-turbine handpiece (CH) had a small disc attached to the bur side spindle and shallow slits around the outer case of the air-turbine handpiece. Centrifugal force produced by this disc together with the labyrinth mechanism inhibits contaminant invasion into the inner chamber and the tube systems.The aim of this study is to investigate the bacterial contamination of air-turbine handpieces clinically, to estimate the effect of 2 countermeasures (PS,CH) and to evaluate the effect of a newly devised "air-turbine handpiece decontaminator with suction". The characteristics of the new decontaminator are follows : 1.The outer surface of the handpiece can be disinfected by 80% ethanol.2.The handpiece can be run for 180 seconds and contaminant be discharged into the suction.The use of PS&CH reduced the internal bacterial contamination to less than 0.2% of the case of non usage. These bacteria can be flashed out completely from the handpiece by 180 senconds, by using the newly devised decontaminator. No bacterial contamination in the air feed tube, exhaust tube, chip air feed tube and water feed tube was detected when PS&CH were used.It is suggested that effective prevention of air-turbine handpiece contamination is achieved by using this newly divised "air-turbine handpiece decontaminator with suction" with PS&CH.