目的·探索机用镍钛根管锉XP-Endo Shaper（XPS）和Reciproc（RC）系统在根管充填物拆除中的效果，为临床应用提供参考依据。方法·纳入2022年3月至9月于上海交通大学医学院附属第九人民医院口腔综合科就诊，因牙周病需拔除患牙的患者，收集其上颌第一恒磨牙具有中度弯曲的近中或远中颊根管共30个，随机分为RC锉组（对照组，n=15）与XPS锉组（试验组，n=15）。2组均先使用M3-PRO镍钛锉进行根管疏通及成形，再使用生物陶瓷糊剂结合单尖法完成根管充填。对照组运用RC锉（R25），试验组采用XPS锉拆除根管充填物。拆除根管充填物前后均使用锥形束计算机断层扫描（cone beam computed tomography，CBCT）进行扫描，对比2组器械拆除根管充填物所需时间、残余根管充填物体积百分比、根尖碎屑推出量以及器械形变情况。采用独立样本t检验和χ²检验比较组间差异。结果·XPS组拆除根管充填物时间为（118.87±18.58）s，较RC组的（107.93±14.79）s长，但2组间比较差异无统计学意义。XPS组残余根管充填物体积百分比为（7.51±8.06）%，较RC组的（15.02±14.63）%低，但组间比较差异无统计学意义。XPS组根尖碎屑推出量为（6.15±1.42）mg，明显少于RC组（8.29±2.01）mg，且差异有统计学意义（P=0.002）。XPS组和RC组的器械均出现了不同程度的形变，但均未发生器械分离。结论·机用镍钛根管锉RC拆除根管充填物更为省时，而XPS的根管清除率较高，且根尖碎屑推出量更小。鉴于根管充填物拆除时间绝对值差异不大，从提高临床疗效、减少术后不良反应的角度考量，机用镍钛根管锉XPS更适用于中度弯曲根管充填物的拆除。

Objective ·To explore the efficacy of the XP-Endo Shaper (XPS) and Reciproc (RC) engine-driven nickel-titanium file systems in removing root canal fillings, and to provide evidence for clinical application. Methods ·The maxillary first permanent molars were obtained from patients who visited the Department of General Dentistry, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, between March and September 2022, which required tooth extraction due to periodontal disease. A total of 30 mesiobuccal or distobuccal root canals with moderate curvature were selected and randomly divided into the RC file group (control group, n=15) and the XPS file group (experimental group, n=15). All root canals were first negotiated and shaped using M3-PRO nickel-titanium files, followed by root canal obturation with bioceramic paste using the single-cone technique. Then, RC files (R25) were used in the control group, while XPS files were used in the experimental group to remove the root canal obturation. Cone Beam Computed Tomography (CBCT) scans were performed before and after the removal procedures. The time required for obturation removal, the percentage of residual obturation volume, the amount of apical debris extrusion, and the degree of instrument deformation were recorded. Independent-sample t-tests and chi-square test were used to compare the differences between the two groups. Results ·The XPS group required slightly more time (118.87±18.58) s than the RC group (107.93±14.79) s, but the difference between two groups was not statistically significant. The XPS group had a lower percentage of residual obturation volume (7.51±8.06)% compared to the RC group (15.02±14.63)%, but the difference was not statistically significant. The XPS group had significantly less apical debris extrusion (6.15±1.42) mg than the RC group (8.29±2.01) mg, with a statistically significant difference (P=0.002). Both groups exhibited varying degrees of instrument deformation, but yet no instrument separation occurred in either group. Conclusion ·The RC engine-driven nickel-titanium files were slightly more time-efficient in removing root canal fillings, whereas the XPS files achieved a higher canal cleanliness and produced less apical debris extrusion. As there was no significant difference in removal time, and considering the superior cleaning performance and reduced risk of postoperative complications, the XPS file system appears more suitable for removing root canal fillings in moderately curved root canals.