Sadegh Khodaee - Dentistry Student, Student Research Committee, Shahed University, Tehran, Iran
Rokhsare Sadeghi - Department of Periodontics, Faculty of Dentistry, Shahed University, Tehran, IR Iran
Ferial Taleghani - Department of Periodontics, Faculty of Dentistry, Shahed University, Tehran, IR Iran
Arash Mahboubi - Dept. of Pharmaceutics, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran

Background and Aim: Nanosilver particles have the potential to serve as a bactericidal agent because of the inherent antimicrobial influences of silver ion .The aim of this invitro study is to evaluate antimicrobial properties of nanosilver against three dental plaque micro-organisms and to compare it with chlorhexidine.Materials and Methods:Nanosilver suspention with concentration of 2000 μg/ml and mean diameter of 18 nanometer was prepared.Antibacterial properties of naosilver and chlorhexidine gluconate 0.12 was primarily evaluated in brain heart infusion agar medium using Cup-plate method against Streptococcus sanguis ATCC 10556 and Streptococcus mutans ATCC 35608. Microdilution method was performed for determining Minimal Inhibitory Concentrations (MIC) and Minimal Bactericidal Concentrations (MBC). The kinetics of bacterial death is assessed by Time-Kill Test in 30 seconds, 1,2,5,10 miniutes time points. Result: The growth inhibition zone diameter was proportional to the antimicrobial agentsconcentration..MIC and MBC of silver nanoparticles were 1.90 and 3.23μg/ml for Streptococcus sanguis, and 3.90and 3.90 μg/ml for Streptococcus mutans..Death kinetic evaluation was demonstrated that in all tested bacterial species, antimicrobial agents were able to reduce bacterial populations significantly after 30 seconds of the contact.Conclusion: Nanosilver had rapid and significant antibacterial effects against dental Plaque microorganisms.

Mouth rinse, Minimal Inhibitory Concentration, Nanosilver