Collagen/fibrin microbeads as a delivery system for Ag-doped bioactive glass and DPSCs for potential applications in dentistry

Silver doped bioactive glass (Ag-BG) and Dental Pulp Stem Cells (DPSCs) have shown promising properties for dental tissue regeneration. This study presents the fabrication and characterization of composite collagen/fibrin microbeads that aimed to incorporate and successfully deliver both Ag-BG and DPSC. Cell viability, cell differentiation in vitro and in vivo, and antibacterial properties of the systems against Escherichia coli (E. coli), Streptococcus mutans (S. mutans) and Enterococcus faecalis (E. faecalis) were evaluated. Cell viability and proliferation of DPSCs within the delivery system were found unaltered in both combinations (Beads/DPSCs and Beads/DPSCs/Ag-BG). Our results show that Ag-BG and DPSCs were successfully incorporated and proliferated within the collagen/fibrin microbeads. DPSCs continued to proliferate up to 6-weeks in cell culture but cell differentiation into odontoblast-like cells was observed only in vivo. The beads containing Ag-BG strongly inhibit bacterial growth in the experimental groups (beads alone, Beads/Ag-BG and Beads/DPSCs/Ag-BG). Our data suggests that collagen/fibrin microbead paste could have clinical applicability in the regenerative dentistry field.