Comparison of the Antibacterial Efficacy and Cytotoxicity of Herbal Nanoparticle-Incorporated Gels on Orthodontic Miniscrews: An In Vitro Study

Background Orthodontic miniscrews are widely used as temporary anchorage miniscrews, but their prolonged stability can be compromised by microbial colonization and associated peri-implant inflammation. While chlorhexidine (CHX) is commonly used for its antimicrobial properties, concerns about its cytotoxicity have led to interest in alternative agents. Herbal extracts like curcumin and cinnamon possess better antimicrobial properties and biocompatibility, especially when formulated as nanoparticles with increased efficacy. Aim The aim of the study is to compare the antibacterial efficacy and cytotoxicity of herbal nanoparticle-incorporated gels on orthodontic miniscrews. Materials and methods In this study, gels containing curcumin and cinnamon nanoparticles were prepared, and 0.2% CHX gels were acquired. Antibacterial efficacy was assessed against <i>Streptococcus mutans</i> using the colony-forming unit (CFU) method. Cytotoxicity effects were assessed using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test. Orthodontic miniscrews were treated with each gel, and results were statistically analyzed using analysis of variance (ANOVA) and post hoc evaluation. Result Cinnamon nanoparticle-incorporated gels had a better antibacterial effect than curcumin nanoparticle-incorporated gel and CHX gel on orthodontic miniscrews. Cinnamon nanoparticle-incorporated gels and curcumin nanoparticle-incorporated gels exhibited the least cytotoxic effect than the CHX gel when applied on orthodontic miniscrews. Conclusion Cinnamon nanoparticle-incorporated gels coated on titanium miniscrews outperformed curcumin nanoparticle-incorporated gel and CHX gel in terms of both antibacterial efficacy and cytotoxicity.