Surface characteristics and in vitro biofilm formation on glass ionomer and composite resin

In the initial stages of dental plaque formation, early colonizing bacteria bind to receptor structures in the pellicle, a proteinaceous film formed i nstantly after cleaning of the tooth surface. Dental restorative materials with surface characteristics different from the tooth might affect pellicle formation and the ability of bacteria to colonize the oral cavity. in this study (i) roughness and chemical composition of glass ionomer and composit e resin surfaces before and after polishing, and (ii) the adsorption of sal ivary proteins and bacterial adherence to the pellicle-coated surfaces were examined. Compared with unpolished composite resin, unpolished glass ionom er had higher surface roughness, contained more inorganic, positively charg ed components, collected more proteins, and promoted better bacterial adher ence. Polishing had the most pronounced effect on the composite resin, givi ng an enlarged and a rougher surface with a more inorganic character. Polis hing the composite resin also led to increased biofilm formation. (C) 2001 Elsevier Science Ltd. All rights reserved.