Antibacterial Efficacy of Resin-Based Dental Composites Modified With Antibacterial Agents Against S. Mutans: A Systematic Review

Introduction: Dental caries caused by Streptococcus mutans is a leading cause of dental restoration failure. Enhancing composite resins with antibacterial agents aims to inhibit bacterial growth and prolong restoration life. Objectives: This review evaluates the anti-bacterial agents efficacy of these modified composites against S. mutans and explores their mechanisms and potential clinical benefits. Methods: A comprehensive literature search was conducted across multiple databases following PRISMA guidelines, focusing on in vitro studies published between 2015 and 2025. Studies evaluating composites with antibacterial additives against S. mutans using standard microbiological assays were included. The quality of eligible studies was assessed using the QUIN tool. Data were synthesized to compare antibacterial strategies and their effects on bacterial suppression and composite properties. Results: Two main antibacterial approaches emerged: contact-killing agents chemically bonded to the resin matrix and release-based nano-fillers that provide sustained antibacterial ion delivery. Both methods showed significant reduction of S. mutans growth, biofilm formation, and acid production while maintaining mechanical integrity when appropriately formulated. Multifunctional composites combining antibacterial and remineralizing features demonstrated enhanced and longer-lasting effects. However, most studies used simplified single-species models under static conditions, with varied methodologies and a lack of standardized dental-specific assays. Conclusions: Resin composites modified with antibacterial agents demonstrate strong potential to inhibit S. mutans and reduce secondary caries risk.