Study of electrochemical corrosion of biocompatible Co-Cr and Ni-Cr dental alloys in artificial saliva. Influence of pH of the solution

The pH of saliva is changeable and variable in the oral environment in function of the quality of foods and liquids ingested. Also, the biocompatibility of a material for dental applications is checked not only by clinical and epidemiological studies, but also by corrosion resistance studies. The aim of this study was to investigate the influence of the pH value of artificial saliva on the corrosion of the Co-Cr and Ni-Cr dental alloys, using different electrochemical techniques such as: cyclic voltammetry, open circuit potential (OCP) measurement, polarization curves and electrochemical impedance spectroscopy (EIS). The obtained results are complementary with scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDXS) analysis, proving that Co-Cr alloy is more resistant in time, and recommending it for successful treatment of patients with dental prosthesis having metal frameworks.