Antibiofilm Efficacy of Clindamycin Loaded Gold Nanoparticles Coated Gutta Percha Evaluated By Crystal Violet Biomass Assay And Surface Roughness Analysis By Atomic Force Microscopy

Abstract

Aims: This study explores the development and evaluation of gutta-percha (GP) cones coated with clindamycin-loaded gold nanoparticles (Clindamycin-AuNPs) to enhance antibiofilm efficacy against Enterococcus faecalis and to characterize surface modifications.

Methods and Material: Gold nanoparticles were prepared by reducing HAuCl₄ with ascorbic acid under alkaline conditions, then loaded with clindamycin to form brick‑red colloids (λ = 250–260 nm). Ten ISO 70 gutta‑percha (GP) cones were soaked in this Clindamycin‑AuNP suspension for 24 h (n = 10), with ten uncoated cones as controls. To test antibiofilm activity, 48 h E. faecalis biofilms (ATCC 51299) were grown in 96‑well plates, exposed to each cone, stained with crystal violet, and quantified by OD readings to calculate viability. Surface roughness (Ra) of coated versus uncoated GP was measured by atomic force microscopy

Statistical analysis used: Data were analyzed in SPSS 26.0. Normality of all variables was confirmed by Kolmogorov–Smirnov and Shapiro–Wilk tests (p > 0.05). Surface roughness and bacterial viability between two groups were compared using independent samples t‑tests. Biofilm biomass (OD readings) across coated GP, uncoated GP, and culture‑only controls was assessed by one‑way ANOVA with Bonferroni post hoc comparisons. Statistical significance was set at α = 0.05.
Results: These findings demonstrate that Clindamycin-AuNP functionalization of GP cones substantially inhibits E. faecalis biofilm formation and alters surface morphology to potentially improve sealer adhesion.
Conclusions: Clindamycin‑AuNP functionalization of GP cones significantly impedes E. faecalis biofilms and alters surface topography, offering a promising strategy to improve root‑canal sealing and antimicrobial performance.