Title : Recent trends in Rotary NiTi instruments metallurgy and fracture prediction
Preparation of curved and anatomical complicated canals have become easy with the advent of rotary nickel titanium instruments. However, the chances of instrument separation have increased. Fractured instruments’ mishaps are critical procedures faced by clinicians during endodontic treatment. It is an unpredictable incident that might prevent adequate cleaning and shaping and compromise the outcome of endodontic treatment especially when the file fractures beyond the apex. Management of a fractured instrument is a sophisticated process and time consuming and sometimes it is impossible.
There are no precise scientific evidence to determine under what conditions a rotary NiTi instrument should be retired. Therefore, an appropriate method for predicting fracture of used rotary NiTi instrument is required. Finding a clinical method for prediction of fracture of NiTi rotary instruments has an outstanding importance that must be considered during endodontic preparation. This study will elect a novel method for investigating the microstructural characteristics of rotary NiTi instrument before fracture happened.In addition, this study will examine a new method to enhance fatigue resistance of rotary NiTi instruments and increase flexibility.