镍钛机用器械循环疲劳的研究进展

Research progress on cyclic fatigue of nickel-titanium rotary instruments

镍钛机用器械与不锈钢器械相比较具有更佳的柔韧性,应用于弯曲根管预备能取得更好的成形和清洁效果,缩短预备时间。但器械折断一直是有待解决的重要问题之一。器械折断的发生会增加根管治疗的难度,甚至导致治疗失败,而器械使用中的循环疲劳是器械折断的主要机制。影响镍钛机用器械循环疲劳的因素很多,包括器械自身因素和外部因素。本文对近年来镍钛机用器械循环疲劳的研究进展进行综述,重点讨论器械循环疲劳的影响因素。

Compared to stainless steel instruments, Ni-Ti rotary instruments are more flexible. They could not only allow for a higher quality of root canal shaping and cleaning, but also decrease the working time when applied in the curved canals. But instrument fracture is still a major concern. Instruments separation may add to the difficulty of the root canal therapy, even lead to the failure of the treatment. Cyclic fatigue is the main mecha- nism for instruments fracture in clinic. Lots of factors influence cyclic fatigue of instruments including internal and external factors. This paper reviewed cyclic fatigue of Ni-Ti rotary instruments in the recent years, with an emphasis on factors influencing cyclic fatigue.