The antimicrobial properties, cytotoxicity, and differentiation potential of double antibiotic intracanal medicaments loaded into hydrogel system

ObjectiveThis study evaluated the antimicrobial properties, cytotoxicity, and mineralization potential of methylcellulose hydrogels loaded with low concentrations of double antibiotic pastes (DAP).Materials and methodsThe direct and residual antibacterial effects of 1, 5, and 10mg/mL of DAP loaded into hydrogels as well as calcium hydroxide (Ca(OH)(2)) were tested against single-species biofilms of Enterococcus faecalis and dual-species biofilms (Enterococcus faecalis and Prevotella intermedia). The effects of DAP hydrogels on proliferation and mineralization of dental pulp stem cells (DPSC) were tested using MTT assays, alkaline phosphate activity (ALP), and alizarin red staining. Fisher's exact tests, Wilcoxon rank sum tests, and one-way ANOVA were used for statistical analyses (=0.05).ResultsAll tested concentrations of DAP hydrogels as well as Ca(OH)(2) demonstrated significant direct antibacterial effects against single- and dual-species biofilms. However, only 5 and 10mg/mL of DAP hydrogels exhibited significant residual antibacterial effects against both types of tested biofilms. Only 1mg/mL of DAP hydrogels did not have significant negative effects on DPSC viability, ALP activity, and mineralization nodule formation. However, 5 and 10mg/mL of DAP hydrogels caused significant negative effects on cytotoxicity and mineralization nodule formation of DPSC.ConclusionsHydrogels containing 1mg/mL DAP offered significant direct antibacterial effects against single- and dual-species biofilms without causing significant negative effects on viability, ALP activity, and mineralization nodule formation of DPSC.Clinical relevanceThe methylcellulose-based hydrogel proposed in this study can be used clinically as a biocompatible system to deliver controlled low concentrations of DAP.