Characterization of the surface of protein-adsorbed dental materials by wetting and streaming potential measurements

In this study we have elucidated the water-wettability and the electrokinetic surface potential of protein-covered dental materials. The proteins used here as typical proteins were human serum albumin and lysozyme from hen's egg. The wettability (hydrophobicity/hydrophilicity) and the surface potential may dominate bacteria] adhesion on the tooth materials and hence influence their biological activity. The artificial tooth materials we investigated were platinum-gold alloy, porcelain and dental resin. Hydroxyapatite was chosen as a reference reflecting natural tooth surface. The wetting was measured by the dropping time method of a thin liquid film along the surface of a protein-covered solid plate sample. The zeta potential was derived from the streaming potential invoked by flowing an electrolyte solution between two parallel sample plates. A variety of surface properties have been found for different combinations of protein and dental material. (C) 2003 Elsevier B.V. All rights reserved.