Effect of heat treatment on cyclic fatigue resistance, thermal behavior and microstructures of K3 NiTi rotary instruments.

Objective: The aim of this study was to investigate the effect of heat treatment on the cyclic fatigue resistance, thermal behavior and microstructural changes of K3 NiTi rotary instruments.

Materials And Methods: Twelve control (as-received) and 12 experimental (heat-treated) K3 NiTi rotary instruments were compared in this study. Those experimental K3 instruments were heated in a furnace for 30 min at 450°C and then quenched in water.