Ahrari، Farzaneh نويسنده Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, , , Eslami، Neda نويسنده Faculty of Pharmacy, Lorestan University of Medical Sciences, Khorramabad, Iran. Eslami, Neda , Rajabi، Omid نويسنده Department of medicinal chemistry, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran , , Ghazvini، Kiarash نويسنده , , Barati، Sahar نويسنده Dentist, Private Practice, ,
Background: Metal nanoparticles have been recently applied in dentistry because of their
antibacterial properties. This study aimed to evaluate antibacterial effects of colloidal solutions
containing zinc oxide (ZnO), copper oxide (CuO), titanium dioxide (TiO2) and silver (Ag)
nanoparticles on Streptococcus mutans and Streptococcus sangius and compare the results with those
of chlorhexidine and sodium fl uoride mouthrinses.
Materials and Methods: After adding nanoparticles to a water-based solution, six groups were
prepared. Groups I to IV included colloidal solutions containing nanoZnO, nanoCuO, nanoTiO2 and
nanoAg, respectively. Groups V and VI consisted of 2.0% sodium fl uoride and 0.2% chlorhexidine
mouthwashes, respectively as controls. We used serial dilution method to fi nd minimum inhibitory
concentrations (MICs) and with subcultures obtained minimum bactericidal concentrations (MBCs)
of the solutions against S. mutans and S. sangius. The data were analyzed by analysis of variance and
Duncan test and P < 0.05 was considered as signifi cant.
Results: The sodium fl uoride mouthrinse did not show any antibacterial effect. The nanoTiO2-
containing solution had the lowest MIC against both microorganisms and also displayed the lowest
MBC against S. mutans (P < 0.05). The colloidal solutions containing nanoTiO2 and nanoZnO showed
the lowest MBC against S. sangius (P < 0.05). On the other hand, chlorhexidine showed the highest
MIC and MBC against both streptococci (P < 0.05).
Conclusion: The nanoTiO2-containing mouthwash proved to be an effective antimicrobial
agent and thus it can be considered as an alternative to chlorhexidine or sodium fluoride
mouthrinses in the oral cavity provided the lack of cytotoxic and genotoxic effects on biologic