Cytocompatibility of titanium metal treated with hydrogen peroxide containing tantalum chloride

摘要

Apatite formation on artificial implants is essential condition to achieve direct boding to bone. We recently showed that titanium metal treated with hydrogenperoxide solution containing tantalum chloride (H_2O_2/Ta) formed an apatite layer on its surface in a simulated body fluid (Kokubo solution). This indicates that the H_2O_2/Ta-treated titanium metal shows bioactivity to bond to living bone. In this study, cytocompatibility of the H_2O_2/Ta-treated specimen was examined, and the results were compared with those for the non-treated titanium and the one treated with 5N-NaOH solution. Osteoblast-like cells (MC3T3-E1) derived from mouse were cultured on the specimens at 36.5deg C under 5percent CO_2 and 95percent humidity. Similar degree of proliferation of the cells was observed at 7 days among the three specimens, while the H_2O_2/Ta-treated titanium after incubation for 5 days showed a lower degree of proliferation than the non-treated titanium and titanium treated with 5N-NaOH. Alkaline phosphatase activity of the cells proliferated on the H_2O_2/Ta-treated titanium was higher than those of the titanium specimens treated with 5N-NaOH, although the degree of proliferation rate was in the order: non-treated titanium > titanium treated with 5N-NaOH > H_2O_2/Ta-treated titanium. These results indicate that the treated titanium with H_2O_2/Ta does not show cytotoxicity and that it rather has high potential for bone formation. The treatment of titanium with H_2O_2/Ta is therefore applicable for providing titanium implants with bioactivity.