RESUMO
Background: Oral health is part of general health. Dental caries is the most common chronic disease worldwide. Considering the significance of plaque control, complications of chemical agents, and the optimal antimicrobial efficacy of nanoparticles, this study aimed to assess the antimicrobial activity of silver nanoparticles (AgNPs) synthesized by the green method using Rhus coriaria L. extract against oral pathogenic microorganisms. Methods: In this in vitro experimental study, Rhus coriaria fruit was dried at room temperature. It was then ground, and its aqueous extract was obtained by the maceration technique. The effects of AgNPs synthesized by the green method in different concentrations were evaluated against Enterococcus faecalis (E. faecalis), Streptococcus mutans (S. mutans), Streptococcus sobrinus (S. sobrinus), Lactobacillus acidophilus (L. acidophilus), and Streptococcus salivarius (S. salivarius) using the well-plate technique. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were also calculated. Data were analyzed by the Wilcoxon test, Kruskal-Wallis test, and Mann-Whitney test. Results: The MIC values were 1024 µg/mL for S. mutans and E. faecalis, and 512 µg/mL for S. sobrinus, S. salivarius, and L. acidophilus. The resistance of S. mutans and E. faecalis was higher than that of S. sobrinus, S. salivarius and L. acidophilus. According to the growth inhibition zones and MBC test results, S. salivarius had the highest resistance to AgNPs followed by L. acidophilus, S. sobrinus, S. mutans, and E. faecalis. Conclusion: AgNPs synthesized by the green method using Rhus coriaria extract was effective against oral pathogenic microorganisms. Thus, they may be used in the formulation of mouthwash and toothpaste.
RESUMO
BACKGROUND: Impressions taken from patients have the potential of cross-transmission of infection among dentistry personnel. The present study aimed to compare the antimicrobial activity of chlorhexidine (CHX) and silver nanoparticles (AgNPs) combined with irreversible hydrocolloid. MATERIALS AND METHODS: This experimental study examined the in vitro antimicrobial effects of irreversible hydrocolloid mixed with silver nanoparticles and chlorhexidine using four groups, namely CHX (0.2%) solution and mouthwash mixed with irreversible hydrocolloid Groups 1 and 2), AgNPs (0.1 and 0.2%) (Groups 3 and 4), and specimens mixed with distilled water as a control group (Group 5) on bacterial strains, namely, Staphylococcu saureu s,Enterococcu sfaecali s,Pseudomona saeruginos a,Escherichi acoli, andStaphylococcu sepidermidi s through disc diffusion method. There were three replications per bacterial species. As data were not normally distributed, Kruskal-Wallis test was used at a significance level of 0.05. RESULTS: No antimicrobial activity was observed in the control groups. In S. aureus, CHX mouthwash had the highest antimicrobial activity, and AgNPs 0.1% and 0.2% groups had lower antimicrobial activity, and there was a significant difference between the two concentrations of AgNPs (P < 0.05). InE.faecali s, the effects of CHX compounds and AgNPs 0.2% were similar to each other and were higher than the effect of AgNPs 0.1% (P < 0.05). In E. coli, CHX compounds exhibited the highest efficacy relative to other materials (P < 0.05), and the AgNPs had no effect. In P. aeruginosa, AgNPs showed the highest growth inhibition zone, which had a significant difference compared to other materials (P ≤ 0.01), whereas the CHX compounds were not effective. InS.epidermidi s, the effect of CHX compounds was similar to one another and was higher than the effect of AgNPs (P ≤ 0.01). CONCLUSION: According to our observations, the antimicrobial activity of AgNPs at 0.1 and 0.2% against five tested bacterial strains was similar to those of pure CHX 0.2% solution and CHX 0.2% mouthwash.