Background and Aim: Effective cleaning and shaping of the root canal system is an essential part of a successful root canal treatment and is considered as one of the basic features of rotary instruments. The present study aimed to compare the efficacy of two types of nickel-titanium rotary files namely BioRaCe and Mtwo, in reduction of Enterococcus faecalis (E. faecalis) count in the root canal system.
Materials and Methods: In this in vitro study, 50 extracted human single-rooted teeth were assigned to two groups plus a positive and a negative control group (20 samples in each group). First, the root canals were sterilized and were then inoculated with E. faecalis (ATCC: 11700). Subsequently, all the root canals were instrumented with BioRaCe and Mtwo nickel-titanium rotary instruments. Then, samples were collected from inside the root canals and cultured in a special medium to evaluate the remaining colonies. The Chi-square goodness of fit test was used to assess the difference in bacterial colony count after root canal preparation with the two rotary systems (alpha=0.05).
Results: Complete bacterial growth was observed in both the BioRaCe and Mtwo groups. There was no statistically significant difference between the two groups regarding bacterial elimination from the root canal system (P>0.05).
Conclusion: Under the limitations of the current study, the two rotary systems exhibited no superiority over each other in terms of their ability to eliminate microorganisms from the root canal system.