Comportement physico - chimique des inserts dentaires

Abstract

A high interest of the dentistry today is focused to improve the fixed or mobile dental prostheses. For this purpose, a large variety of metal alloys is employed, returning of this fact difficult to evaluate their technical, biological and clinical properties. Nickel chromium is widely used as a restorative material in dentistry but its biocompatibility is of concern as there are reports of patients suffering adverse effects caused by exposure to nickel-based restorations. The aim of this work was to evaluate the electrochemical behavior of a commercial alloy (Ni –Cr) before and after heat treatments simulated a porcelain-fused-to-metal firing process and was to evaluate the effect of variations of pH and of the mediums on the electrochemical behavior. Before and after the heat treatments, alloy specimens were examined for their microstructure, hardness, electrochemical properties of corrosion, and for this reason one used various methods of characterizations which are: the diffraction of X-rays, optical Microscopy, microhardness and electrochemical measurements. Research was carried out by using several mediums of several PH: citric acid, artificial saliva and NaCl