Biocompatibility evaluation of dental metal alloys in vitro: Expression ofextracellular matrix molecules and its relationship to cell proliferation rates

The biocompatibility in vitro of dental biomaterials has been widely studie d, with consideration of cell viability and cell proliferation rates. In th e present study we evaluated the biocompatibility in vitro of three single- phase dental metal alloys, all provided by the same manufacturer. To this a im, we considered the percentage of proliferating cells revealed by 5-bromo deoxyuridine incorporation in human fibroblast cultures in the presence of these biomaterials, performing a short time test (72 h). These data were co rrelated with immunocytochemical expression of four molecules of the extrac ellular matrix, i.e., fibronectin, type I collagen, beta(1)-integrin subuni t, and chondroitin sulfate, because the capability of cells to adhere to su bstrata is widely related to cell proliferation rates. Alloys presenting hi gher amounts of noble elements were more biocompatible even when they conta ined significant amount of both Ag and Cu. As regards the expression of the extracellular matrix molecules, the organization level of fibronectin in f ibrils was correlated with higher cell proliferation rates, whereas no diff erence was detected for the expression of the other antigens. On these base s, we assume that expression of fibronectin could be a useful parameter in evaluation of biocompatibility in addition to cell proliferation capability . (C) 2000 John Wiley & Sons, Inc.