Assessment of the Effect of the Ionic Implantation by Plasma Immersion on the Flexibility of the Nickel-titanium Endodontic Fi

Due to its pseudo elastic behavior, the nickel-titanium (nitinol) alloy has been used in the manufacture of endodontic instruments in recent years, being especially useful for curved canals preparation. Extensive research has been carried out to improve the wear resistance of the nitinol instruments without create modifications in the bulk of the files. The purpose of this work was to measure the flexibility of commercially available type K stainless steel and nickel-titanium endodontic files, submit the nitinol files to plasma immersion ion implantation and assess the treatment effects on the same property. The instruments flexibility was measured throughout the bending moment test at 30 and 45 according to the American Dental Association specification n 28. The hardness of the files was measured before and after treatment by the Vickers method. The instruments surface state was observed throughout scanning electronic microscopy and the surface chemical composition of treated instruments was determined throughout the X-Rays photoelectron spectroscopy. The results found have led to the conclusion that no statistically significant change on the instruments flexibility was observed after the plasma immersion ion implantation. Key-words: endodontic files, nickel-titanium, ionic implantation.