Effect of Cryogenic Treatment on Fracture Resistance of Nickel Titanium Rotary Instruments a Systematic Review

Abstract

Introduction: Endodontic instruments upon rotation are subjected to both tensile and compressive stresses in curved canals. This stress is localized at the point of curvature. It has been demonstrated that the continuous cycle of tensile and compressive forces in the area of curvature of the canal to which (Nickel Titanium) NiTi rotary instruments are subjected produce a very destructive form of loading, causing cyclic fatigue and eventually fracture of the instrument.2 The aim of this study is to conduct a systematic review on the effect of cryogenic treatment on fracture resistance of nickel titanium rotary instruments.