PhD Scientific Days 2025

Dental Research

Antibacterial Effect of Chitosan on Oral Bacteria

Name of the presenter

Róna Virág

Institute/workplace of the presenter

Fogpótlástani Klinika

Authors

Dr. Virág Róna¹

1: Fogpótlástani Klinika

Text of the abstract

Introduction
Chitosan, a natural cationic polysaccharide derived from chitin, has gained increasing attention for its antimicrobial properties. Due to its positive charge, biocompatibility, and biodegradability, chitosan can interact with negatively charged bacterial cell membranes, disrupting their integrity, and inducing bacterial apoptosis. This electrostatic interaction leads to membrane disruption and cell death. Given its bioactivity, chitosan has been explored as a preventive agent against oral diseases such as dental caries and endodontic infections.

Aims
To investigate the antibacterial effects of chitosan on Streptococcus mutans and Enterococcus faecalis.

Method
Two systematic reviews and meta-analyses were conducted. The first evaluated the efficacy of chitosan-containing chewing gums on Streptococcus mutans levels (DOI: 10.3390/ijms242015270). A systematic search in PubMed, EMBASE, and Cochrane Library identified randomized controlled.
The second meta-analysis investigated chitosan's antibacterial effect on Enterococcus faecalis using in vitro studies from the same databases.

Results
Meta-analysis 1: Out of 6758 articles, four met inclusion criteria (three included in quantitative synthesis). Chitosan significantly reduced S. mutans counts, with a mean difference of -4.68 × 10⁵. The random-effects model interval was [-2.15 × 10⁶; 1.21 × 10⁶]; prediction interval: [1.03 × 10⁷; 9.40 × 10⁶]. Heterogeneity was high (I² = 98%, p = 0.35).
Meta-analysis 2: From 889 records, 10 studies were included. For CFU/mL outcomes, the overall effect was -0.28 (CI: [-1.54, 0.97]). In the subgroup analysis: for chitosan concentrations <1%, the effect was -7.35 (CI: [-27.27, 12.56]); for ≥1%, the effect was -0.90 (CI: [-19.24, 17.45]). While the effects were not statistically significant, the trend suggests potential inhibitory action against E. faecalis.

Conclusion
Chitosan is a promising natural antimicrobial agent against S. mutans and E. faecalis, both key pathogens in oral infections. Further studies are needed to standardize concentrations and delivery methods for clinical applications.

Funding
This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.