In Vitro Cytotoxicity Assessment of Selenium Nanoparticle-Coated Gutta-Percha Cones for Enhanced Endodontic Biocompatibility

Abstract

Background: Successful root canal treatment depends on thorough cleaning, disinfection, and effective obturation of the root canal system. Persistent microorganisms, particularly Enterococcus faecalis, can survive conventional treatment and lead to endodontic failure. Selenium nanoparticles (SeNPs) possess potent antibacterial activity and low cytotoxicity, making them promising agents for enhancing the antimicrobial properties of gutta-percha (GP) cones.

Aim: To evaluate the in vitro cytotoxicity of SeNP-coated gutta-percha cones using human gingival fibroblasts (HGFs) and assess their biocompatibility compared to conventional uncoated GP.

Methodology: SeNPs were synthesized via chemical reduction and coated onto size 40 GP cones after surface activation. Primary HGFs were exposed to eluates from SeNP-coated GP and uncoated GP for 24, 48, and 72 hours. Cytotoxicity was assessed using MTT and Live/Dead assays. Cell viability and morphology were analyzed using a microplate reader and fluorescence microscopy, respectively.

Results: MTT assay showed high cell viability across all groups, with SeNP-coated GP maintaining approximately 101% viability compared to 95.8% for uncoated GP and 100% for controls. Live/Dead assay confirmed predominantly green fluorescence in the SeNP-coated group, indicating excellent cell viability and normal fibroblast morphology. No significant cytotoxicity was observed for either SeNP-coated or uncoated GP.

Conclusion: SeNP-coated gutta-percha demonstrated excellent biocompatibility and maintained or slightly enhanced cell viability compared to uncoated GP. Coupled with their known antibacterial properties, SeNP-coated GP may serve as a safe and effective modification to improve the antimicrobial performance of root canal fillings. Further in vivo studies are warranted to confirm clinical applicability.