Methods for Removing Fractured Endodontic Instruments in Root Canal: A Brief Systematic Review

Abstract
Introduction: In the scenario of endodontic treatment, fracture of the instrument complicates the endodontic procedure by obstructing debridement, delaying the completion of treatment, and affecting the patient's dental experience. When a file fractures during root canal treatment, several treatment options are available. Fractured endodontic instruments inhibit optimal cleaning and filling of root canals. Objective: To carry out a brief systematic review study to present the main clinical outcomes of different types of techniques for removing fragments of endodontic instruments in root canals. Methods: The rules of the Systematic Review-PRISMA Platform were followed. The research was carried out from November 2020 to January 2021 and developed based on Scopus, PubMed, and SCIENCE DIRECT. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results: A total of 132 articles were found involving the removal of fragments of endodontic instruments. A total of 80 articles were evaluated in full and 30 were included and evaluated in the present study. It has been found that the probability of successful removal of a fractured instrument is reported to range from 53 to 95%, with more than 80% of fractured instruments being removed by the use of ultrasound. Also, long fragments (0.4 mm) can adsorb ultrasonic energy and hinder its loosening. Nickel-titanium (NiTi) instruments with their pseudo-elasticity, especially the newly developed heat-treated NiTi instruments are more ductile and flexible compared to conventional NiTi2. Conclusion: Fractured instruments can be removed by a variety of methods, such as good ultrasonic tips, microtubule devices, and hemostatic pliers/forceps. Removing a fractured file is associated with considerable risk, and therefore the fragment must be circumvented. A cost-benefit analysis of the treatment should be considered before selecting a definitive treatment for the patient.