Anti-Adherence and Antimicrobial Activities of Silver Nanoparticles against Serotypes C and K of Streptococcus mutans on Orthodontic Appliances

Abstract

Background and Objectives: Streptococcus mutans (S. mutans) is the main microorganism associated with the presence of dental caries and specific serotypes of this bacteria have been related to several systemic diseases limiting general health. In orthodontics, white spot lesions (WSL), represent a great challenge for clinicians due to the great fluctuation of their prevalence and incidence during conventional orthodontic treatments. Although silver nanoparticles (AgNP) have been demonstrated to have great antimicrobial properties in several microorganisms, including S. mutans bacteria, there is no available information about anti adherence and antimicrobial properties of AgNP exposed to two of the most relevant serotypes of S. mutans adhered on orthodontic materials used for conventional therapeutics. The objective of this study was to determine anti-adherence and antimicrobial levels of AgNP against serotypes c and k of S. mutans on conventional orthodontic appliances. Materials and Methods: An AgNP solution was prepared and characterized using dispersion light scattering (DLS) and transmission electron microscopy (TEM). Antimicrobial and anti-adherence activities of AgNP were determined using minimal inhibitory concentrations (MIC) and bacterial adherence testing against serotypes c and k of S. mutans clinically isolated and confirmed by PCR assay. Results: The prepared AgNP had spherical shapes with a good size distribution (29.3 ± 0.7 nm) with negative and well-defined electrical charges (−36.5 ± 5.7 mV). AgNP had good bacterial growth (55.7 ± 19.3 µg/mL for serotype c, and 111.4 ± 38.6 µg/mL for serotype k) and adherence inhibitions for all bacterial strains and orthodontic wires (p < 0.05). The serotype k showed statistically the highest microbial adherence (p < 0.05). The SS wires promoted more bacterial adhesion (149.0 ± 253.6 UFC/mL × 104) than CuNiTi (3.3 ± 6.0 UFC/mL × 104) and NiTi (101.1 ± 108.5 UFC/mL × 104) arches. SEM analysis suggests CuNiTi wires demonstrated better topographical conditions for bacterial adherence while AFM evaluation determined cell wall irregularities in bacterial cells exposed to AgNP. Conclusions: This study suggests the widespread use of AgNP as a potential anti-adherent and antimicrobial agent for the prevention of WSL during conventional orthodontic therapies and, collaterally, other systemic diseases.

Antimicrobial and Antibiofilm Effects of Silver-Copper Nanoparticles Obtained by Green Synthesis Against Streptococcus mutans

“…In the study by Espinosa-Cristóbal et al, Ag NPs exhibited greater antimicrobial effects on S. mutans at lower concentrations than gold or zinc [ 2 ]. In a study by Valodkar et al, Ag-Cu NPs showed antimicrobial effects on gram-positive and gram-negative bacteria [ 21 ].…”

“…According to the World Health Organization's Global Oral Health Status Report for the year 2022, oral diseases have a significant impact on approximately 3.5 billion people worldwide, with approximately 75% of those affected residing in middle-income countries both in developed and economically disadvantaged countries, dental caries remain a significant public health concern [ 1 ]. Following the identification of Streptococcus mutans ( S. mutans ) as the causative agent of dental caries, considerable attention has been directed towards targeting this bacterium in disease prevention efforts through the use of antimicrobial agents and vaccine development [ 2 ]. In conclusion, there is a need for a substance that does not promote bacterial resistance and exhibits strong bactericidal properties.…”

Effect of the addition of silver nanoparticles on the mechanical properties of an orthodontic adhesive

“…In particular, silver nanoparticles (AgNP) have exhibited significant antibacterial activity against cariogenic bacteria ( Sánchez-Tito and Tay, 2021 , Yassaei et al, 2020 ). Additionally, the anti-adherence properties of AgNP have been tested, and they are effective in inhibiting the adhesion of S. mutans on the surface of orthodontic materials ( Nafarrate-Valdez, et al, 2022 ).…”

Antibacterial, Anti-Biofilm and Pro-Migratory Effects of Double Layered Hydrogels Packaged with Lactoferrin-DsiRNA-Silver Nanoparticles for Chronic Wound Therapy

“…AgNPs are heavily utilized in research settings for their antimicrobial properties and have demonstrated promising results even against resistant bacterial strains [ 7 , 8 , 9 , 10 ]. AgNPs offer numerous advantages as antimicrobial agents in terms of their adherence and penetration ability toward the cell surface of bacteria [ 11 , 12 , 13 ]. In addition, AgNPs that are stabilized by chitosan (CS) provide avenues for complexation with biological molecules, such as deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), via their phosphorus and sulfur donor ligands [ 14 , 15 ].…”