Evaluation of Antimicrobial Effect of Biologically Safe Selenium Nanoparticles-coated Clear Aligner—An In vitro Study

To synthesize selenium nanoparticles (SeNPs) from plant extract, characterize them, coat them on clear aligners, and evaluate their cytotoxicity and antimicrobial activity. The green synthesis of SeNPs utilized the leaves of Withania somnifera. The biosynthesized nanoparticles are incorporated in clear aligners using sol-gel thin film dip coating method to check for antimicrobial effect against Streptococcus mutans and Lactobacillus species using time kill curve assay. The cytotoxicity of the material was checked using brine shrimp lethality assay. The optical density values indicated that the SeNPs-coated clear aligners effectively inhibited the growth of Lactobacillus sp. and S. mutans. Time kill curve assessed in varying concentration of 25 µg/mL, 50 µg/mL, and 100 µg/mL revealed greater antibacterial activity at a lower concentration with increasing time. Clear aligners coated with SeNPs had positive antibacterial effects on suspensions of Lactobacillus sp. and S. mutans and are biocompatible.