Antibacterial and biocompatibility properties of bioactive glass and double antibiotic-loaded hydrogels in regenerative endodontic treatment.

This study evaluated the antibacterial and biocompatibility effects of Gelatin Methacrylate Hydrogel (GelMA) loaded with a double antibiotic paste (DAP) and bioactive glass (BG). The cellular impact of 1 mg/mL (1DAP) and 5 mg/mL (5DAP) DAP, as well as 1% BG (1BG) and 10% BG (10BG) within the hydrogel on dental pulp stem cells (DPSCs), was assessed using ATP cell viability and alkaline phosphatase (ALP) assays over 21 days. Antibacterial efficacy against E. faecalis was measured with and without dentin disks after 24-hour incubation, followed by colony-forming unit (CFU) counting. The statistical analysis was performed using one- and two-way ANOVA and Kruskal-Wallis tests. Results indicated that 5DAP and 10BG significantly reduced the vitality of DPSCs compared to 1DAP, 1BG, GelMA alone, and the control group (p < 0.001). Conversely, 1DAP and 1BG demonstrated the highest cell viability, with 1BG exhibiting superior ALP activity (p < 0.001). In the absence of dentin disks, 10BG and 5DAP displayed the greatest antibacterial effects (p < 0.001). However, the presence of dentin significantly diminished the antibacterial efficacy of BG, with 5DAP showing the strongest effect on infected dentin disks (p = 0.008). GelMA with 1% BG enhanced cellular functions. Dentin significantly reduced the antibacterial efficacy of BG, regardless of concentration. DAP at 5 mg/mL provided the highest antibacterial activity on infected dentin disks. However, none of the hydrogels completely eliminated bacteria from the dentin disks.