THE INFLUENCE OF DENTAL METAL-ALLOYS ON CELL-PROLIFERATION AND FIBRONECTIN ARRANGEMENT IN HUMAN FIBROBLAST-CULTURES

biocompatibility of six single-phase dental metal alloys was studied b y determining cell proliferation rates correlated to the arrangement o f fibronectin (FN) in fibroblast cultures. Immunocytochemical methods were used to detect cell proliferation by 5-bromodeoxyuridine (BrdU) i ncorporation, and FN organization [i.e. diffuse in the extracellular m atrix and organized in fibrils or in focal adhesions (FA)] in human fi broblast cultures. Cell proliferation rates were related to FN arrange ment and in particular a higher percentage of cells in the S-phase was related to a predominance of FA. The greatest difference in behaviour compared to that of the controls was detected after 120 and 168 hr: a t these times, as well as at previous ones, the alloy with the highest Au content seemed the most biocompatible among those tested, as it be haved in a very similar way to the controls. In contrast, fibroblasts exposed to the other five alloys showed different behaviours from the controls. It is assumed that a correlation exists between FN organizat ion and the percentage of BrdU-positive cells, and that these features vary in the presence of different alloys. The observation of FN arran gement together with cell proliferation rates could be another useful tool in determining the biocompatibility of dental metal alloys. (C) 1 997 Elsevier Science Ltd.