REDUCED PLAQUE ACCUMULATION ON HYDROCARBON THIN-FILM DEPOSITED ON RESTORATIVE ACRYLIC POLYMERS

The deposition of a thin polymeric film from ethylene plasma was used to modify the surface properties of acrylic teeth, commonly used in th e dental practice for crown and bridge restorations. The effects of th e surface modification process on the surface composition, morphology, and energetics were evaluated by electron spectroscopy for chemical a nalysis, atomic force microscopy, and contact angle measurement respec tively. Plaque accumulation on the plasma-coated and untreated materia l was evaluated in in vivo experiments, in which the same patient rece ived conventional and plasma-coated restorations. The hydrocarbon-like surface of the plasma-coated restoration remained remarkably free fro m plaque, even in the absence of brushing. On the other hand, plaque a ccumulation was observed on the unmodified restoration. Results are di scussed according to recent theories on bioadhesive phenomena. (C) 199 7 John Wiley & Sons, Inc.