Objective: The aims of the study are to investigate effect surface treatment process on prolonging life rotary instruments against cyclic fatigue and coating corrosion resistance Ni-Ti files.Methods: This was carried out in two stages. In first one, a total 120 (25/.04 taper) from 3 brands (HeroShaper, RaCe, TF) were selected. Sixty them anodized then all tested simulated root canals with diffe...