Aim: To compare the dentinal damage induced by stainless steel hand files and rotary nickel-titanium instruments using ProTaper Next, K3XF and Mtwo.
Materials and Method: Fourty single-rooted premolars were selected. All specimens were decoronated and divided into four groups, each group having 10 specimens. Group 1 specimens were prepared by Hand K-files (Mani), Group 2 with ProTaper Next (Dentsply Maillefer), Group 3 with K3XF (Sybron Endo) and Group 4 with Mtwo (VDW, Munich, Germany). Roots of each specimen were sectioned at 3, 6 and 9mm from the apex and were then viewed under a stereomicroscope to evaluate presence or absence of dentinal defects.
Results: On comparison of all different Ni-Ti rotary file systems in respect to dentinal damage; groups were significantly different from each other (P = 0.012). Group 1 (Hand files) showed no dentinal defects. Dentinal defects were found in the ProTaper Next, K3XF and Mtwo rotary groups. But the difference was non-significant when comparison was done among ProTaper Next, K3XF and Mtwo rotary group.
Conclusion: All rotary files induced increased changes of dentinal defects as compared to hand instrumentation