Antimicrobial sensibility of Streptococcus mutans serotypes to silver nanoparticles Article uri icon


  • Dental caries is a common infectious disease in humans all over the world and is considered a public health problem with an incidence and prevalence still high. The principal pathogen associated with the development of dental caries is Streptococcus mutans (S. mutans), a microorganism that has been widely studied. A new approach to treat dental caries is the use of silver nanoparticles (SNP) due to their antibacterial effect. It has been reported the effectiveness of SNP against S. mutans, but sensibility of S. mutans serotypes to SNP is still unknown. The aim of this study is to analyze the inhibitory effect of three different sizes of silver nanoparticles on S. mutans obtained from clinical isolates and one reference bacteria strain, determining sensibility differences between serotypes, which were determined by using PCR analysis. Silver nanoparticles with sizes around 9.3, 21.3 and 98 nm were prepared, characterized and used to find, with a microdilution method, the minimum inhibitory concentration (MIC) on S. mutans. SNP showed bactericidal effect on all strains tested with statistical differences between smaller nanoparticles and larger nanoparticles, 9.3 nm SNP showed a higher antibacterial activity than 21.3 and 98 nm SNP; however, sensibility was different among all clinical strains (p < 0.05) being serotype c the most sensible and serotype e the most resistant to the three different sizes of SNP considering the inhibitory effect better when nanoparticle size is smaller. © 2012 Elsevier B.V. All rights reserved.

publication date

  • 2012-01-01