EVALUATION OF CYCLIC FATIGUE RESISTANCE OF ROTARY NITI VS CONTROLLED MEMORY ENDODONTIC FILE SYSTEMS: AN IN-VITRO STUDY
The purpose of this study was to compare fracture resistance of Hyflex CM, Hero Shapers and Vortex NiTi file systems due to cyclic fatigue in curved canals. The methodology in this study involved testing the cyclic fatigue of endodontic root canal file rotating at 375 rpm. A simulated model was created such that, the instrument will bend at 60 degrees during function, maximum curvature being 5 mm from the tip of the file. The number of rotations till the instrument fractured was recorded by mathematical formula. The results were statistically analyzed. Hyflex CM performed significantly better than Vortex & Hero Shapers file system. However there was no statistically significant difference observed between Vortex & Hero Shapers file system in terms of cyclic fatigue.
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