Objective: We developed a family of bioactive glasses that reliably adhere onto titanium alloy while retaining bioactivity according to the well established in vitro assay in simulated body fluid (SBF). However, bioactive glasses may react differently in solutions that more closely represent the in vivo environment, such as SBF containing proteins. The objective was to test the hypothesis that the presence of proteins in SBF has no effect on bioactive glasses reactivity. Methods: Two glass compositions, 6P50 and 6P55 were prepared. Samples1.5 x 1.5 x 0.3cm were cut and polished through 1mm with water based diamond suspension, cleaned by sonication in acetone and isopropyl alcohol for 5min and sterilized by dry heat @ 250°C for 1hour. Samples were placed in sterile 12-well tissue culture plates. Solutions (non pyrogenic water, SBF, SBF + 1% fetal calf serum (FCS), and SBF + 10% FCS) were prepared and filter sterilized (0.22mm). 2mL of solution was added to each sample. Samples were stored for 7 days @37 °C and 5%CO2 atmosphere. They were gently rinsed with water, placed in a desiccator overnight, and sputtered with Au-Pd for SEM analysis at 9000x. Images were ranked by an independent observer, with value 1 for the sample showing the least precipitate on the surface, and increasing numbers for more precipitate. Statistical analysis was Kruskal-Wallis. N=4 per sample per solution except SBF + 1% FCS where N=3. Results: All samples in SBF had precipitates on their surfaces. The samples immersed in SBF + 10% FCS had significantly less precipitate on their surfaces (p<0.05 for glass 6P50 and p<0.005 for glass 6P55). Conclusion: The presence of proteins significantly decreased the precipitation of hydroxyapatite-like mineral on bioactive glasses, challenging the validity of the well established test in SBF. Supported by NIH/NIDCR Grant R01DE 11289.

Back to the Dental Materials: III - Ceramics and Cements Program
Back to the 32nd Annual Meeting and Exhibition of the AADR (March 12-15, 2003)

Top Level Search