FlexMaster镍钛机用器械根管再治疗清理效果的体外研究

In vitro study of the efficacy of FlexMaster NiTi rotary instruments in root canal retreatment

目的研究FlexMaster镍钛机用器械根管再治疗清理的效果。方法选取临床拔除的40颗单根管前牙,用改良式逐步后退法进行根管预备,牙胶尖与碧兰糊剂侧方加压充填根管。放置30d后随机分为两组,A组用H型锉去除根管内旧充填物,B组用FlexMaster镍钛机用器械去除充填物。分别记录操作时间。然后,将牙根纵劈,立体显微镜下观察根管冠1/3、根中1/3和根尖1/3段的残留物情况。结果在根管冠1/3处两种方法的根管清理效果无统计学差异(P>0.05)。在根管的中段和根尖段,B组的残留物量较A组少,两组间存在显著性差异(P<0.05)。B组操作时间明显少于A组,两组间也有显著性差异(P<0.01)。结论与手用H型锉相比,FlexMaster镍钛机用根管预备器械去除根管旧充填物效果更好,且操作时间显著减少。

Objective To study the retreatment effectiveness of FlexMaster NiTi rotary instruments. Methods 40 extracted single-rooted anterior teeth were divided into two groups, 20 in each. They were instrumented by modified step- back flare technique and obdurated with gutta-percha and cortisomol sealer using lateral condensation. Retreatment of group A was performed by H files, group B by using FlexMaster NiTi rotary instruments. The time of retreatment was recorded. The teeth were then split longitudinally into halves. The remaining gutta-percha/sealer on the apical , middle, coronal parts of the root canal walls were visually scored with a stereomicroscope. Results In the apical and middle sections,less resid- ual filling material was observed in group B than in group A（ P 〈 0.05 ）. The mean operating time of group B was signifi- cantly less than that of group A. Conclusions The retreatment effectiveness of FlexMaster is better than that of H files.