Dissolution of nickel-titanium endodontic files via an electrochemical process: a new concept for future retrieval of fractured files in root canals

Abstract

Introduction: The 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.

Methods: Current 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.

Results: The 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.

Conclusions: The 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.