Assessment of cariogenic biofilms using drug encapsulated hydrogel membrane

Abstract

Dental caries is a multifactorial disease primarily driven by cariogenic biofilms. Current antimicrobial treatments lack sustained release and localized action, leading to reduced efficacy and potential microbial resistance. Hydrogel-based drug delivery systems offer a promising alternative due to their biocompatibility, tunable properties, and ability to provide controlled antimicrobial release.

Objective: This study aimed to develop, characterize, and evaluate the efficacy of a chlorhexidine digluconate (CHX)-encapsulated chitosan-alginate hydrogel membrane against Streptococcus mutans and Lactobacillus acidophilus biofilms.
Methods: Hydrogel membranes were synthesized via ionic cross-linking and characterized using Scanning Electron Microscopy (SEM), Fourier-Transform Infrared Spectroscopy (FTIR), swelling studies, and drug release kinetics. Biofilms were grown on hydroxyapatite discs, and the antibacterial efficacy was assessed through zone of inhibition, Minimum Biofilm Inhibitory Concentration (MBIC), colony-forming unit (CFU) counts, and confocal laser scanning microscopy (CLSM). Biocompatibility was evaluated using an MTT assay on human gingival fibroblasts.
Results: The hydrogel membrane exhibited a uniform porous structure with a high swelling ratio (350±25%) in simulated saliva and sustained CHX release over 72 hours. A significant reduction in biofilm viability (>90%) was observed compared to controls (p<0.001). CLSM images confirmed extensive biofilm disruption. The hydrogel showed no cytotoxicity to human gingival fibroblasts.

Conclusion: The CHX-encapsulated hydrogel membrane effectively inhibited cariogenic biofilms while maintaining biocompatibility, demonstrating its potential as a novel, sustained-release platform for caries prevention and management.