(PO114) The Antibacterial Effect of Bioceramic Root Canal Sealers Against Multi-Species Dental Biolfilm in a Novel Ex Vivo Model

Abstract: Bioceramic materials possess antibacterial properties; however, it is challenging to compare them due to variations in experimental designs. This study aimed to evaluate the antibacterial effect of five bioceramic sealers using a novel ex vivo model and to investigate whether the method of application influenced their antibacterial effect. The ex vivo model was fabricated using an artificial root canal with a standardized slot in the apical portion that allowed fitting of precisely cut dentin. Forty-eight dentin blocks were infected with multi-species bacteria by centrifugation. Thirty-six samples of 3-week-old biofilm were subjected to EndoSequence BC Sealer (BC), AH Plus Bioceramic Sealer (AHBC), Bio-C Sealer (BIOC), BioRoot Flow (BRF), and C-root SP (CR) in the model. After 1, 4, and 8 weeks, antibacterial efficacy was determined by viability staining and confocal laser scanning microscopy. Twelve samples were subjected to BC and AHBC as open-faced specimens. Antibacterial efficacy was determined after 1 and 4 weeks. Data were analyzed using one-way ANOVA and Tukey’s post hoc test (p < .05). The results showed at 1-week sealer exposure, CR and AHBC produced significantly more killed bacteria than BC, BRF, and BIOC. While AHBC’s antibacterial activity significantly decreased at 4 weeks, the activity of all other sealers fluctuated slightly. At 8 weeks, CR and BC yielded significantly more killed bacteria. No significant difference was found between model specimens and open-faced specimens. Antibacterial activity of bioceramic sealers was dynamic, and all tested sealers had a long-lasting antibacterial effect against multi-species biofilm in dentinal tubules. The method of sealer application had no influence on antibacterial effect.