[Electrochemical evaluation of the alloy cobalt-chromium in a synthetic salivary solution]

The removable prosthesis, odontological speciality which has as a role the replacement of the absent teeth, generally uses removable metal prostheses. These prostheses are made of alloys in which cobalt occupies a significant proportion. Being placed in an electrolytic (saliva) and biological (bacteria) medium, they are prone to degradation by phenomena of corrosion. In order to study in vitro the electrochemical behavior of the alloy cobalt-chromium, we subjected this metal part to anodic polarization in a synthetic salivary solution.

The electrochemical study was carried out at the biophysics laboratory of Casablanca medicine faculty. The equipment used for the voltamperometric study being voltalab PGZ 100 version 4.05 with the voltamaster 4 software.

The results were collected in the form of potentiometric curves and of polarization curves, witch enabled us to determine the corrosion resistance of the alloy cobalt-chromium in salivary medium.

Our work highlighted that the acidity of the salivary solution has a negative effect on the alloy cobalt-chromium and that the surface quality gotten by a good polishing takes part to reinforce the corrosion resistance.