Efficacy of hyaluronic acid on the inhibition of periodontal bridging organisms Fusobacterium nucleatum and Prevotella intermedia: An in vitro study.

Abstract

Objective: This in vitro study aimed to evaluate the antimicrobial effects of high-molecular-weight hyaluronic acid (HA) against two key periodontal bacteria, Prevotella intermedia and Fusobacterium nucleatum. These organisms play an important role in biofilm formation and disease progression in periodontitis.

Materials and methods: Standard laboratory strains of P. intermedia (ATCC 25611) and F. nucleatum (ATCC 25568) were cultured in anaerobic conditions. HA with different molecular weights (141 kDa, 757 kDa, and 1,300 kDa) was tested at concentrations from 0.5 to 2.0 mg/ml. The minimum inhibitory concentration was determined through serial dilution in thioglycollate broth. Each test was performed in triplicate. Turbidity after 48-72 h of incubation served as an indicator of bacterial growth. Statistical significance was analyzed using G*Power with α = 0.05 and 80% power.

Results: HA showed concentration-dependent bacteriostatic effects. P. intermedia showed growth inhibition at 1 mg/ml, whereas F. nucleatum required 2 mg/ml for similar inhibition. Concentrations below these amounts did not inhibit growth. These findings suggest that HA may disrupt adhesion and nutrient uptake needed for bacterial growth and biofilm formation.

Conclusion: High-molecular-weight HA shows potential as a nonantibiotic support agent in periodontal therapy by selectively inhibiting key anaerobic bacteria involved in biofilm development. Its two actions, antimicrobial and immunomodulatory, highlight its importance by breaking down pathogenic cooperation and supporting periodontal healing. Further research with multispecies biofilms, clinical isolates, and host interaction models is necessary for clinical application.