Effect of heat treatment on the centering ability and dentin removal of a nickel–titanium single file rotary system

Abstract

Aim The aim of this study was to investigate the effect of heat treatment on the centering ability and amount of dentin removal of OneShape single file rotary system (OS) by cone beam computed tomography. Materials and methods Twenty human premolars with single root canals were allocated into two equal groups (n = 10) according to the used rotary system: group 1: OS system, group 2: One Curve which is heat-treated OS single file rotary system. Preinstrumentation and postinstrumentation images were obtained at 3, 6, and 9 mm from the apex and assessed to determine canal centering ability. Amount of removed dentin was estimated by difference between preinstrumentation and postinstrumentation root canal volumes. Data were analyzed using t-test and significance level was set at P value less than or equal to 0.05. Results The results showed that One Curve file has higher mean centering ratio and more dentin removal than OS file with no statistically significant difference between them (P > 0.05). Conclusion It was concluded that heat treatment did not have significant effect as both files could maintain the original canal path without significant differences in centering ability and amount of removed dentin.