R-Endo镍钛机动根管再治疗器械去除根管内充填物的体外研究

The efficacy of R-Endo NiTi rotary and stainless-steel hand instruments to remove root filling material in root canal retreatment

目的评价R-Endo根管再治疗系统用于根管再治疗的清理效果。方法选择离体单根管前牙30颗,用冠向下法预备根管,热牙胶垂直加压技术充填后随机分为两组,分别用以下器械去除根管内充填物:A组为R-Endo根管再治疗器械,B组为不锈钢手用锉。记录每颗牙的操作时间。然后将牙体沿颊舌向纵劈,体视显微镜下观察各组样本根管壁充填物的残留情况。结果两组器械均不能完全去除根管内充填物。在根冠1/3和根中段,两组的根管壁上残留充填物比较的差异无统计学意义(P>0.05);但在根尖1/3,A组残留充填物较B组少(P<0.05)。两组操作时间的差异有统计学意义(P<0.01)。结论 R-Endo镍钛机动根管再治疗器械能有效去除根管内充填物并减少操作时间。

Objective To evaluate the efficacy of R-Endo NiTi rotary and stainless-steel hand instruments to remove root filling material in root canal retreatment. Methods Thirty single-root canal teeth were prepared with crown-down technique and filled with warm vertical compaction technique. The teeth were divided into two groups randomly. The root canal filling materials were removed by the following devices and methods： R-Endo NiTi rotary files （group A） and stainless steel files with chloroform （group B）. The time for retreatment was recorded. The teeth were split along vertical direction. The stereo microscope was used to evaluate the remnants within two groups of the root canals. The difference between two groups was compared with the statistical analysis. Results Two groups were not completely removed root filling materials. There was no significant difference between group A and B in the coronal and middle third of canal. But in the apical third of canal, Group A was significantly clearer than group B （P〈0.05）. The operating time of group A was significantly faster than group B （P〈0.01）. Conclusion R Endo NiTi rotary retreatment system is effective in removing root filling materials and can reduce the operating time.