Anti-bacterial Efficacy of Zirconium Oxide Nanoparticles on Streptococcus mutans and Enterococcus faecalis: An In...

Introduction Complex interactions between cariogenic bacteria and host factors modulate dental caries. Streptococcus mutans, a gram-positive facultative anaerobe plays a prominent role in the initiation of caries. The ability of S. mutans to adhere to salivary enamel pellicle results in an acidic local habitat for the organism. This leads to demineralization of the tooth and penetration of bacteria into the pulp leading to endodontic infections. Enterococcus faecalis, an opportunistic pathogenis a gram-positive, facultative anaerobe implicated in secondary endodontic infections. This study aimed to evaluate the anti-bacterial efficacy of zirconium oxide nanoparticles (ZrO₂ NPs) against S. mutans and E. faecalis. Materials and methods Standard S. mutans and E. faecalis strains were subcultured at specific temperatures for 24 hours. S.mutans was subcultured onto blood agar and colonies of E. faecalis were cultured on nutrient agar. The strains were tested for their sensitivity to ZrO₂ NPs at various dilutions. The standard methods determined the minimum concentration of ZrO₂ NPs to inhibit 99.9% growth of S. mutans and E. faecalis. Results The zones of inhibition were compared with gentamicin as a control. ZrO₂ NPs exhibited clear zones of inhibition of 12 mm and 15 mm at 100 mg/mL concentrations against S. mutans and E. faecalis in the agar wells, respectively. Conclusion The present study concluded that ZrO₂ NPs have potential anti-bacterial activity against both S. mutans and E. faecalis.