HYDROGEN-PEROXIDE TOWARD ENHANCED OXIDE-GROWTH ON TITANIUM IN PBS SOLUTION - BLUE COLORATION AND CLINICAL RELEVANCE

Oxide films formed on titanium exposed to a phosphate-buffered saline solution with and without hydrogen peroxide (H2O2) addition were inves tigated by means of electrochemical impedance spectroscopy (EIS) and X -ray photoelectron spectroscopy (XPS). The oxide growth at the titaniu m/electrolyte interface was monitored in situ by daily EIS measurement s during periods of several weeks. The results suggest that the oxide film can be described by a two-layer model with a barrier inner layer and a porous outer layer. H2O2 addition results in an increased dissol ution/oxidation rate that leads to an enhanced oxide growth of the por ous outer layer. As a result, the total oxide film can reach a thickne ss corresponding to an interference blue color. Based on XPS results, H2O2 addition furthermore seems to facilitate the incorporation of pho sphate ions into the thicker porous layer. This observation may be rel ated to the so-called osseointegration properties of titanium. (C) 199 6 John Wiley & Sons, Inc.