Shaping, and disinfecting abilities of ProTaper Universal, ProTaper Gold, and Twisted Files: A correlative microcomputed tomographic and bacteriologic analysis

Abstract

Aim: The purpose of this study was to assess the canal shaping ability and reduction of Enterococcus faecalis (E. faecalis) by ProTaper Universal (PTU), ProTaper Gold (PTG), and Twisted File (TF) systems, using microcomputed tomography (μCT). Methods: Distobuccal canals of 36 extracted human maxillary molars were inoculated with E. faecalis American Type Culture Collection 29212 for 28 days. Thirty-three specimens (three excluded due to contamination) were randomly divided into three groups with 11 specimens in each group, according to the instrumentation system that was utilized: PTU, PTG, and TF. Sterile distilled water was used as the irrigant during preparation. Paper points had been used to collect samples from the root canals both pre- and postpreparation, and bacterial quantification was done to examine the bacterial reduction. Pre- and postinstrumentation μCT scanning of roots were done to analyze the shaping ability. Results: After preparation, all three techniques significantly lowered the amount of E. faecalis while also significantly increasing the canal volume (P < 0.001). Intergroup comparison of the % of bacterial reduction and uninstrumented area disclosed no significant differences (P > 0.05), whereas the increase in canal volume of the PTU was significantly higher than PTG and TF, and that of the PTG was significantly higher than TF. Conclusion: It may be concluded, within the constraints of this in vitro study, that PTG and TF had better shaping ability than PTU, whereas no difference was found in their ability to reduce bacterial load.