Influence of nanohydroxyapatite mouthwash on the growth of Candida albicans biofilm on milled denture surfaces: An in vitro study

Purpose: There is a need for effective solutions for the persistent prevalence of denture stomatitis (DS) in denture-wearing populations. This study assessed the impact of nanohydroxyapatite (nanoHAP) nanoparticles on Candida albicans biofilm formation on milled polymethylmethacrylate (PMMA) denture bases.

Materials and methods: Acquired salivary pellicle was formed on disks milled from a prepolymerized PMMA puck. The disks were assigned to two groups, A (n = 18) and B (n = 18), and each group was further subdivided into three subgroups (6/subgroup), each treated with either Polident solution (antibacterial denture cleanser), nanoHAP mouthwash, or distilled water. Disks in group A subgroups were soaked in their respective treatment solutions for 8 h, followed by biofilm formation on the disk for 24 h. Disks in group B subgroups had C. albicans biofilm formed on them for 24 h, followed by soaking in their respective treatment solutions for 8 h. Biofilm thickness, biomass, and live/dead cell ratio were determined using a confocal laser scanning microscope. Biofilm morphology was examined with a scanning electron microscope (SEM). Data were analyzed by ANOVA and Tukey-Kramer multiple comparisons (α = 0.05).

Results: In group A, nanoHAP mouthwash displayed significant anti-adhesive properties. In group B, biofilm biomass and thickness significantly decreased (p < 0.05), with the nanoHAP showing the most substantial reduction in existing biofilm compared to other solutions, but it did not significantly affect cell viability.

Conclusions: This study demonstrated the efficacy of nanoHAP mouthwash in inhibiting C. albicans biofilm formation when used as a storage medium for acrylic dentures. It suggests its potential clinical application for preventing denture stomatitis in patients.