摘要
[Objectives]This study is to investigate the difference in the comprehensive effects of the two types of machine-used nickel-titanium(ni-ti)instruments in removing root canal filling materials to provide guidance for clinical applications.[Methods]We selected 60 single-tube premolars and randomly divided them into a P group(ProTaper ni-ti file group)and a K group(K3 ni-ti file group).The root canal was prepared according to the uniform standard crown cutting and manual k-file stepwise regression method.The root canal was fully filled and the X-ray film was taken.X-rays were taken again after re-treatment.The removal rate of the root filler material was obtained using Auto CAD 2000 image analysis software.[Results]We found no statistical difference in the clearance and total time of the two nickel-titanium devices in removing the gum filling material.Both the ProTaper ni-ti file and the K3 ni-ti file were able to remove most of the root canal filling during root canal retreatment.[Conclusions]There was no significant difference between the two devices in clinical applications.
