Cyclic fatigue resistance of different continuous rotation and reciprocating endodontic systems.

OBJECTIVE The objective of this study is to compare the cyclic fatigue resistance of nine types of endodontic instruments of nickel-titanium. MATERIALS AND METHODS Five files of 25 mm of length of each group: Reciproc (RC) R25; WaveOne (WO) Primary; Unicone (UC) L25 25/0.06; K3XF 25/0.06; ProTaper Universal F2 (PTF2); ProTaper Next X2 (PTX2); Mtwo 25/0.06; BioRaCe 25/0.06; One Shape L25 25/0.06 were subjected to a cyclic fatigue resistance test on a mechanical apparatus. The mean fracture time was analyzed statistically by one-way analysis of variance and Tukey's honest significant difference post hoc test, with significance set at P< 0.05. CONCLUSION It was observed that the groups PTX2, RC, R25, UC L25 25/0.06, and WO Primary presented greater cyclic fracture resistance than the other groups (P< 0.001).