Antibacterial, Antibiofilm Activity, and Biocompatibility of Eco‐Friendly Chamomile‐Mediated Silver Nanoparticles Against Oral Pathogens Associated With Periodontal Disease

Silver nanoparticles (Ag NPs) have attracted attention for use as novel antimicrobial agents to reduce bacterial dental plaque. Ag NPs were synthesized using the green synthesis method with aqueous extract of Matricaria chamomilla L. The structure, optical, and morphological properties were extensively investigated in response to the variation of reducing, capping, and stabilizing agents containing chamomile extracts, with their antibacterial performance evaluated against oral pathogens Porphyromonas gingivalis and Streptococcus mutans . Surface plasmon resonance peaks are observed at 415 nm and 436 nm for the green and commercial Ag NPs, respectively, confirming the formation of Ag NPs. The results indicated that the biosynthesized Ag NPs were spherical with an average particle size of 55.39 nm and had comparable properties to commercially synthesized Ag NPs but were more efficient in terms of higher specific surface area (143 m ² /g) and better colloidal stability (zeta potential: −41.13 mV). Ag NPs synthesized using the green procedure also exhibited strong antimicrobial activity with minimum inhibitory concentrations (MICs) of 150 μg/mL against S. mutans and 50 μg/mL against P. gingivalis and demonstrated maximum inhibition zone diameters of 35 mm and 28 mm against S. mutans and P. gingivalis , respectively. In the antibiofilm assay, the green‐synthesized Ag NPs achieved biofilm inhibition efficiencies of 91.93% against S. mutans and 91.16% against P. gingivalis at the highest tested concentration. The cytotoxicity test by MTT assay on human gingival fibroblasts showed dose‐dependent effects with an IC ₅₀ value of approximately 440 μg/mL for green‐synthesized Ag NPs, compared with approximately 110 μg/mL for commercial Ag NPs. Green synthesis mediated by chamomile yielded biocompatible, stable, and potent antibacterial Ag NPs that represent a promising candidate for future applications in the management of periodontal diseases with low cytotoxic effects on healthy cells. However, since the present findings are based exclusively on in vitro experiments, further in vivo and clinical studies are required to validate their safety, efficacy, and therapeutic potential before clinical application can be considered. Furthermore, this study provides a comprehensive comparative evaluation of chamomile‐mediated and commercially available Ag NPs, demonstrating that the green‐synthesized nanoparticles exhibit superior physicochemical characteristics, enhanced antimicrobial and antibiofilm activities, and improved biocompatibility, thereby highlighting their potential as a sustainable alternative for periodontal applications.