Evaluation of antibacterial and biocompatibility of radiopaque bioactive glass-based endodontic cements

This study evaluated the antibacterial properties, hemocompatibility, cytotoxicity, and genotoxicity of bioactive glass ceramic-based endodontic cement formulated with various radiopaque active ingredients with varying concentrations (0, 15, and 20 wt%). Antibacterial activity against E. faecalis was assessed using colony-forming unit (CFU) assays. The results showed significant antimicrobial activity of the bioactive glass-based cement, which was enhanced by adding radiopaque active ingredients. Lanthanum oxide exhibited the highest antibacterial activity at a concentration of 20 %, reducing the CFU count from 6,000,000 (control) to 1,190,000. Bismuth oxide and samarium oxide also showed dose-dependent improvements in antibacterial properties. Hemocompatibility analysis revealed that all cement samples, including those containing radiopaque agents, remained nonhemolytic after 1-h- and 24-h incubation, indicating excellent compatibility with human blood. Cell viability testing with the L929 cell line showed that the cement samples achieved the required cell viability threshold of 70 % according to ISO 10993-5:2009 over 1, 3, and 7 days of exposure. Genotoxicity assessment using comet assay revealed no detectable DNA damage in the cement samples compared to the negative control. These comprehensive results confirm the biocompatibility and strong antibacterial properties of the bioactive glass ceramic-based endodontic cement samples containing various radiopacity agents.