Electrochemical Research on the Corrosion of Orthodontic Nickel-Titanium Wires

Electrochemical corrosion tests were performed on the NiTi alloy used as orthodontic wires. The experimental setup had to be carefully designed in order to maximise the usefulness of the data produced. Also the maximum amount of data was to be collected on a single run experiment to deal with the non-reproducibility generally encountered doing corrosion studies. The corrosion potential, polarisation resistance and corrosion current are discussed. Impedance analysis provided information as to the nature of the passive behaviour of the material.