Electroanalysis of nickel ions released in artificial saliva from three orthodontic arch wires: Stainless Steel (SS), NiTi, and CuNiTi

Background: Nickel titanium wires are superior for first alignment because they have exceptional shape memory and super-elasticity. Increased concerns have been raised about the high rate of nickel (Ni) allergy and the growing usage of dental biomaterials that contain Ni. Aim: The aim of the study was to analyze and evaluate the rate of nickel release from different types of orthodontic arch wires. Materials and methods: A set of arch wires of nickel titanium (NiTi), SS and Cu-NiTi were immersed in artificial saliva for three days and analyzed after three days. The amount of Ni ions released from the sample were evaluated using electrochemical techniques such as Cyclic Voltammetry (CV), Electrochemical Impedance Spectroscopy (EIS) and polarization (Tafel) plot. Results: The EIS and Tafel graph confirmed the s-NiTi, s-CuNiTi showed an excellent corrosion resistance than the s-SS. From all the above measurements, we can conclude that the saliva can affect the corrosion resistance property of the SS, NiTi, CuNiTi day by day. Conclusion: From this study it was concluded that the saliva can affect the corrosion resistance property of the SS, NiTi, CuNiTi day by day, and there was nickel ion release but at a very negligible rate