Boessler Claudia, Paque Frank, Peters Ove A
Department of Preventive Dentistry, Division of Endodontology, University of Zurich, Center for Dental Medicine, Switzerland.
J Endod. 2009 Jan;35(1):102-6. doi: 10.1016/j.joen.2008.09.008. Epub 2008 Oct 25.
Surface modifications of nickel-titanium instruments such as electropolishing may reduce fracture incidence but could potentially alter the instruments' mechanical properties. We studied the impact of two surface types, machined and electropolished, of ProTaper shaping files on torque and force during simulated root canal preparation. Pilot holes of 0.5-mm diameter were drilled perpendicularly through 3-mm thick human dentin discs and served as standardized simulated root canals (SSRCs). A total of 300 SSRCs were prepared with ProTaper Sx, S1, and S2 instruments using an automated testing platform. Maximum torque (in Ncm) and maximum force values (in N) were measured. In three experimental groups (Sx, S1, and S2) preparation of SSRCs was performed using electropolished versus machined instruments in the same dentin disc. For all three tested instruments, peak torque was higher for electropolished files; apically exerted forces were similar, except for Sx, in which machined instruments developed higher forces. We conclude that surface treatment by electropolishing alters the cutting ability of nickel-titanium rotary instruments.
镍钛器械的表面改性（如电解抛光）可能会降低折断发生率，但也可能改变器械的机械性能。我们研究了ProTaper成型锉的两种表面类型（机加工和电解抛光）在模拟根管预备过程中对扭矩和力的影响。在3毫米厚的人牙本质盘上垂直钻出直径0.5毫米的引导孔，作为标准化模拟根管（SSRC）。使用自动测试平台，用ProTaper Sx、S1和S2器械对总共300个SSRC进行预备。测量最大扭矩（单位：Ncm）和最大力值（单位：N）。在三个实验组（Sx、S1和S2）中，在同一牙本质盘中使用电解抛光器械与机加工器械进行SSRC的预备。对于所有三种测试器械，电解抛光锉的峰值扭矩更高；除Sx外，根尖施加的力相似，Sx中机加工器械产生的力更高。我们得出结论，电解抛光表面处理会改变镍钛旋转器械的切削能力。
