Abstract
Since bioactive glass used in dental implants is known to bond to the jawbone by forming a calcium-phosphate and silica-rich layer on the surface of the glass, the author investigated the biological activities of the bioactive glass having a surface layer which was formed in vitro. The bioactive glass was immersed in a RPMI 1640 medium for 10 days to form this layer, and its formation was confirmed with the aid of an energy-dispersive X-ray analysis.
Results showed that both the control as well as the calcium-phosphate and silica-rich layered bioactive glass have no toxic effect on L 929 cells. On the other hand, lipopolysaccharide (LPS)-induced 3H-thymidine uptake by mouse spleen cells were not influenced by the bioactive glass having a calcium-phosphate and silica-rich layer, but was reduced by the intact bioactive glass. Furthermore, the bioactive glass had no effect on LPS-induced interleukin 1α production by human peripheral mononuclear cells, but the intact bioactive glass enhanced the production. These results suggest that the bioactive glass having a calcium-phosphate and silica-rich layer to be bioinert, which is contrary to the intact bioactive glass.
