三种单只成形镍钛器械对模拟弯曲根管预备效果的评价

目的 比较３种单只成形镍钛器械对模拟弯曲根管切割能力和成形能力，为其临床应用提供依据。 方法 选取40个单弯树脂模拟根管，随机分为Reciproc Blue组、WaveOne Gold组、M3-L组和ProTaper Gold组，每组各10个。按照使用说明书预备各组模拟根管，记录模拟根管预备时间、预备前后模拟根管的质量差、模拟根管弯曲角度差、根尖偏移量、模拟根管内外径树脂去除量和模拟根管定心比。 结果 WaveOne Gold组模拟根管预备时间短于其他3组（Ｐ<0.05），ProTaper Gold组模拟根管预备时间较其他3组明显增长（Ｐ<0.05）；预备前后4组模拟根管质量差比较差异无统计学意义（Ｐ>0.05）。预备前后M3-L组模拟根管弯曲角度差小于其他3组（Ｐ<0.05）；预备后4组模拟根管根尖区（1~4 mm）外径树脂去除量大于内径（Ｐ<0.05），根中区（5~8 mm）内径树脂去除量较外径大（Ｐ<0.05）；在距离根尖孔1、3和6 mm处，ProTaper Gold组模拟根管的定心比与1的差值最大，大于其他3组（Ｐ<0.05），其他组模拟根管各个观察点处定心比与1的差值比较差异无统计学意义（Ｐ>0.05）。 结论 Reciproc Blue、WaveOne Gold和M3-L３种单只成形镍钛器械均可较好地保持根管的形态，且较ProTaper Gold多只锉系统的预备效率和中心定位能力更好。国产单只镍钛器械M3-L可以更好地保持根管原有的弯曲度。

Evaluation of preparation effect of three kinds of single formed nickel-titanium instruments on simulated curved root canals

Objective To compare the cutting abilities and shaping abilities of three kinds of single formed nickel-titanium instruments for the simulated curved root canals， and to provide the basis for their clinical applications. Methods A total of 40 single curved resin simulated root canals were selected and randomly divided into Reciproc Blue group， WaveOne Gold group， M3-L group， and ProTaper Gold group， and there were 10 single curved resin simulated root canals in each group. The simulated root canals in each group were prepared according to the user manuals， and the preparation time， difference in weights of simulated root canals before and after preparation， difference of bending angles of simulated root canals，apical deviations， removal amounts of internal and external resin， centering ratios of simulated root canals in various groups were recorded. Results The preparation time of the simulated root canals in WaveOne Gold group was shorter than those in the other three groups （P<0.05），and the preparation time of the simulated root canals in ProTaper Gold group was longer than those in the other groups（P<0.05）. There was no significant difference in wieight of the simulated root canals among four groups before and after preparation （P>0.05）.The differences of bending angles of the simulated root canals in M3-L group before and after preparation was smaller than those in the other three groups （P<0.05）.After preparation， the removal amount of internal resin of the apical zone （1－4 mm） was larger than extermal resin（P<0.05）， and the removal amount of external resin of the middle zone （5－8 mm） was larger than internal resin（P<0.05）； at the positions 1， 3 and 6 mm from the apical foramen， the differences between the centering ratios of the simulated root canal in ProTaper Gold group and 1 was the largest， which was larger than those in the other three groups （P<0.05），and the differences between the centering ratio of the simulated root canals and 1 at each observation point in the other groups were not statistically significant （P>0.05）. Conclusion Reciproc Blue， WaveOne Gold and M3-L single formed nickel-titanium instruments can keep the shape of root canals better， and have better preparation efficiencies and center positioning ability than the ProTaper Gold multi-file system. Domestic single nickel-titanium instrument M3-L can better maintain the original curvature of the root canals.