Department of Endodontics and Restorative Dentistry, University of Siena, Siena, Italy.
Int Endod J. 2012 Jan;45(1):1-6. doi: 10.1111/j.1365-2591.2011.01932.x. Epub 2011 Aug 16.
To compare the effectiveness of two Ni-Ti systems and hand files for removing gutta-percha and sealer from root canals.
The root canals of 60 single-rooted human teeth were prepared, filled with gutta-percha and sealer (Pulp Canal Sealer; SybronEndo, Orange, CA, USA). Specimens were then divided into three groups (n=20), and root filling material was removed using MTwo Retreatment Files (group 1); R-Endo (group 2); K-files and Gates-Glidden drills (group 3). After retreatment, the efficacy of each technique was assessed using radiographs that were later digitized and the images analysed using AutoCAD 2004. The percentage of residual gutta-percha was calculated for the whole canal as well as for the coronal, middle and apical thirds. Time required, apically extruded debris and the number of fractured instruments were also recorded. Data were statistically analysed using Kruskal-Wallis and Mann-Whitney U-tests.
All instrumentation techniques left gutta-percha and sealer remnants inside the root canals. Ni-Ti systems were significantly faster (P < 0.05) than the manual technique and significantly more effective (P < 0.05) in removing gutta-percha particularly from the middle and apical thirds of the root canal. R-Endo instrumentation was significantly more effective (P < 0.05) than MTwo retreatment files in removing gutta-percha from the middle and apical thirds. R-Endo instruments were associated with the least number of cases of apical extrusion. One MTwo instrument fractured.
The Ni-Ti systems were more effective and faster than hand files, although all techniques left gutta-percha and sealer remnants on the root canals.
比较两种镍钛系统和手动器械去除根管内牙胶和密封剂的效果。
对 60 颗单根人牙的根管进行预备，并用牙胶和密封剂（牙髓根管密封剂；SybronEndo，Orange，CA，美国）填充。然后将标本分为三组（n=20），使用 MTwo 再治疗锉（组 1）；R-Endo（组 2）；K 锉和 Gates-Glidden 扩孔钻（组 3）去除根充材料。再治疗后，使用 AutoCAD 2004 对每张射线照片进行数字化和图像分析，以评估每种技术的效果。计算整个根管以及冠、中、根尖三分之一的牙胶残留百分比。记录所需时间、根尖挤出的碎屑量和折断器械的数量。使用 Kruskal-Wallis 和 Mann-Whitney U 检验对数据进行统计学分析。
所有器械技术都在根管内留下了牙胶和密封剂的残余物。镍钛系统比手动技术明显更快（P < 0.05），且去除牙胶特别是从中、根尖三分之一根管的效果明显更好（P < 0.05）。R-Endo 器械在去除中、根尖三分之一根管内的牙胶方面明显比 MTwo 再治疗锉更有效（P < 0.05）。R-Endo 器械与根尖挤出的病例数最少有关。有一个 MTwo 器械折断。
镍钛系统比手动器械更有效、更快，尽管所有技术都在根管内留下了牙胶和密封剂的残余物。
