Cyclic fatigue and energy-dispersive X-ray spectroscopy examination of the novel ROTATE instrument.

To investigate the cyclic fatigue resistance of novel ROTATE instruments and to compare with the same size of One Curve, TF adaptive, and Mtwo instruments using a root canal simulation model. Four-type of 25/0.06 instruments were used: ROTATE, Mtwo, One Curve, TF adaptive. Instruments were divided into two subgroups: Distilled water and 2.5% sodium hypochlorite (n = 20). Instruments were operated at 35°C. The time to fracture and the length of the fractured fragments were compared One-way analysis of variance (ANOVA) followed by Tukey's multiple comparison tests (p < .05). Descriptive analysis was performed for the elemental composition of instruments by Energy-dispersive X-ray spectroscopy. ROTATE demonstrated the lowest Ni content and SD values. ROTATE had significantly higher NCF values than other groups (p < .0001). Sodium hypochlorite was decreased the mean NCF values. This is the first study in the literature on the cyclic fatigue of ROTATE. ROTATE presented higher cyclic fatigue life than One Curve, TF Adaptive, and Mtwo.