新型单支锉根管预备系统对卵圆形根管成型和清理能力的对比研究

目的：比较 Reciproc（RE）、OneShape（OS）、ProTaper（PT）3种根管预备系统对卵圆形根管的清理和成型能力的差异。方法：选择57个离体下颌第一磨牙的远中根管，分组后分别用上述3种系统进行根管预备并记录操作时间，电镜下观察根管预备后根管壁上的碎屑和玷污层，比较3种系统对卵圆形根管的清理能力。在预备前后进行 Micro-CT 扫描，对比3种系统对卵圆形根管的成型能力。结果：根管预备后，扫描电镜下，根尖部评分显示 PT 组清理能力低于 RE 组和 OS 组（P ＜0．05）；根的冠部、中部无显著差异。三维根管重建图像分析显示，OS 组在预备前后根管形态各项参数（体积、表面积、范围、最大直径和最小直径）的改变量低于 RE 组和 PT 组（P ＜0．05），PT 组预备前后的根管弯曲度改变量高于 RE 组和 OS 组（P ＜0．05）。RE 组和 OS 组的根管预备时间低于 PT 组（P ＜0．05）。结论：RE 和 OS 在根管预备效率、根管清理能力以及保持根管原始走向方面均优于 PT。OS 与 RE 在清理能力上无明显差异，而 OS 对根管的切割成型能力要低于 RE 和 PT。

Comparision of the shaping and cleaning ability of Reciproc,OneShape and ProTaper rotary instrument in oval-shaped canal of extracted teeth

Objective:To investigate the shaping and cleaning ability of Reciproc(RE),OneShape(OS)and ProTaper(PT)in oval-shaped root canal preparation.Methods:The canals of 57 distal roots of mandibular first molars were randomly divided into 3 groups and prepared by RE,OS and PT respectively.The preparation time was recorded.After instrumentation,all root canal walls were examined under SEMand evaluated by scores of debris and smear layer.The 3D data and images of the roots of pre-and post-preparation were con-structed by Micro-CT scanning.Results:Group RE and OS showed lower scores of debris and smear layer than those in group PT at the apical level(P <0.05),and less preparation time (P <0.05).Before and after preparation,the changes of root canal morphological pa-rameters (including volume,surface,area,major diameter and minor diameter)in OS group were less than those in group RE and PT(P<0.05).The changes of canal curvature in group PT was larger than that in group RE and OS (P <0.05).Conclusion:RE and OS are more effective than PT in debridement and faster in root canal preparation.RE and OS can maintain the centering of original canal better than PT in the apical part of the root canal.The shaping ability of OS is weaker than that of RE and PT.