Evaluation of cyclic fatigue resistance of four heat-treated nickel-titanium single file systems in canals with single curvature - An in-vitro study

The anatomy of root canal system has a complex variation, so it is important to have a flexible system that would require minimal preparation of the canal. Nickel-titanium (NiTi) instruments can be separated and broken without previous warning during the root canal preparation, and this separation has been a problem. However endodontic instruments are unable to achieve a complete clean to the root canal system because of many high variability of root canal system complex anatomy, the endodontic instruments which are chosen for root canal preparation play a critical role in accomplishing the main goal for obturation and for the prevention of ledging, zipping,root canal transportation, file separation, and save the root canal original shape, NiTi instruments properties of memory shape, super elasticity, and resistance to torsional and cyclic fatigue are advantages to their use in preparation of the curved root canal. This study aims to compare the cyclic fatigue resistance of four heat treated nickel-titanium single file systems in Reciprocation movement and rotary movement in curved canals.