Dissolution of Nickel-Titanium Endodontic Files via an Electrochemical Process: A New Concept for Future Retrieval of Fractured Files in Root Canals

IntroductionThe retrieval of fractured instruments from root canals has been largely reported in the literature. However, a less complex retrieval method that causes minimum damage to the dental structures is needed. The aim of this article is to introduce a new concept of retrieval of fractured instruments from root canals based on an electrochemical process.MethodsCurrent register tests were used to evaluate the dissolution process of 25.04 nickel-titanium (NiTi) K3 rotary files. A constant anodic potential was applied to the NiTi files, whereas the Potentiostat registered the anodic current. After the tests, all files were observed by using an optical microscope.ResultsThe current attained initial values of approximately 55 mA that declined during the entire test. A good reproducibility of results was observed. The optical microscopy analysis evidenced a progressive consumption of the files with increasing polarization time.ConclusionsThe results presented here show that the concept of fractured file retrieval by an electrochemical process is feasible. This concept resulted in a consistent basis for the development of a method to remove fractured instruments from root canals.