Effectiveness of Cellulose Nanofibers Addition to Soft Denture Lining Material on Candida albicans Adherence and Physical and Mechanical Properties

Current denture liner materials suffer from low tear strength, poor abrasion resistance, weak bond strength to denture material, and increasing risk of denture stomatitis due to adherence of Candida albicans. The aim of this study was to evaluate the effects of the addition of cellulose nanofibers (CNFs) to commercial soft denture liner material on the adherence of Candida albicans and physical and mechanical properties.

CNFs at concentrations of 0.0, 0.5, and 1.0 wt.% were incorporated into a soft liner material. Antifungal effects were assessed by quantifying the adherence of Candida albicans. The Shore A hardness, tensile strength, peel bond strength, and surface roughness tests were employed to assess the properties of the denture liner materials. Chemical interactions between the fibers and liner material were confirmed by Fourier Transform Infrared (FTIR) spectroscopy, and a Scanning Electron Microscope (SEM) was used to assess the CNFs particles and fractured surface morphology.

There was a statistically significant decrease in the adherence of Candida albicans in both experimental CNFs groups. FTIR spectroscopic analysis confirmed the existence of strong hydrogen bonding between the CNFs and the liner polymer matrix. The hardness, surface roughness, peel bond strength and tensile strength increased significantly due to the addition of CNFs, most notably at 0.5 wt.%.

The addition of CNFs to the denture liner material improved mechanical properties and reduced Candida albicans adherence even with increased surface roughness above the established threshold of Ra ≥ 0.2 μm. The 0.5 wt.% CNFs concentration provided the most favorable balance of enhanced antifungal activity and mechanical properties, which suggests that CNFs may have altered surface interactions or adhesion sites and have the potential for clinical use in the mitigation of denture stomatitis.