机用镍钛器械ProTaper Next和ProTaper Universal在模拟根管内成形的能力

Shaping ability of ProTaper Next and ProTaper Universal Ni-Ti rotary endodontic instruments in simulated root canals

背景:目前机用镍钛锉尚无国际统一标准,应用于临床的几种镍钛系统在横截面形态、锥度变化、组成数量、中心钢量及切割刃角度等方面均有独特设计,使其清理成形能力、安全性能、切割效率等方面存在差异。ProTaper Next是在ProTaper Universal基础上的改良及创新,其在组成数量、刃部横截面形态、与根管壁接触点及尖端锥度等方面均进行了改进。目的:利用树脂模拟根管比较机用镍钛器械ProTaper Next和ProTaper Universal在弯曲根管内的成形能力。方法:使用机用镍钛器械ProTaper Next和ProTaper Universal采用冠向下法预备两组模拟树脂根管,预备过程中记录预备时间和器械变形及分离的发生,预备结束后使用Adobe Photoshop v7.0软件测量根管内外侧壁树脂去除量,并计算器械中心定位力。结果与结论:两组器械形变方面差异无显著性意义;ProTaper Next预备时间较ProTaper Universal明显缩短(P<0.05)。两组根管预备后中下段均有部分偏移。ProTaper Next X2在根管弯曲内侧在大多数测量点切割的树脂量少于ProTaper Universal F2(P<0.05)。ProTaper Next在大多数测量点的中心定位能力好于ProTaper Universal(P<0.05)。结果证实,两组镍钛器械ProTaper Next和ProTaper Universal均能较好地完成根管预备;在预备根管中下段时,都会造成一定程度上的偏移,但ProTaper Next的中心定位力总体上较ProTaper Universal好。

BACKGROUND：Currently, the nickel-titanium file has no uniform international standards for clinical use, and several nickel-titanium systems have unique designs in terms of cross-sectional shape, taper change, composition number, central steel volume, and cutting edge angle, so there are some differences in cleanup capability, security, and cutting efficiency. ProTaper Next is developed based on the ProTaper Universal, and its composition number, blade cross-sectional shape, contact point with the root canal wal and the tip tapers are al improved. OBJECTIVE：To compare the shaping ability between ProTaper Next and ProTaper Universal Ni-Ti rotary endodontic instruments by preparing the simulated root canals. METHODS： Two groups of resin blocks were prepared by ProTaper Next and ProTaper Universal respectively. Preparation time and incidence of canal aberration and instruments failure were recorded. After preparation, the images taken before and after preparation were superimposed and analyzed by software Adobe Photoshop v7.0. We measured the amount of resin removed at the inner and outer canal wals. The centering ability was also assessed. RESULTS AND CONCLUSION：There was no difference in the incidence of canal aberration. ProTaper Next was faster than ProTaper Universal to prepare canals （P 〈 0.05）. Both instruments caused apical transportation. ProTaper Universal F2 removed more materials than ProTaper Next X2 at the inner canal wals （P 〈 0.05）. ProTaper Next showed better centering ability than ProTaper Universal in most levels （P 〈 0.05）. Two instruments showed good performance in preparation but both created some apical transportation. However, the ProTaper Next was better in maintaining the original form of curved canal with safety and higher efficiency.