Incorporation of polymethyl methacrylate (PMMA) - cerium (Ce) nanofibers into acrylic resin for removable denture bases: evaluation of physical-mechanical properties, cytotoxicity, and antifungal activity.

OBJECTIVE

This study aimed to synthesize and characterize polymethyl methacrylate (PMMA) - cerium (Ce) nanofibers and investigate the effect of their incorporation on the biological, physical-mechanical properties and cytotoxicity of PMMA acrylic resin for removable denture bases.

METHODS

PMMA-Ce nanofibers produced by solution blown spinning with different concentrations of Ce (5%, 10%, 15%, and 20%) were evaluated for activity against Candida albicans and characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, thermogravimetry, differential scanning calorimetry, and inductively coupled plasma optical emission spectroscopy (ICP-OES). Different proportions of nanofibers (0, 0.5, 1, 2.5, and 5 wt%) were incorporated into PMMA and characterized by SEM, ICP-OES, and thermogravimetry. Samples were evaluated for antifungal activity, flexural strength, Knoop microhardness, surface roughness, contact angle, color parameters (L*, a*, and b*), and cytotoxicity. Data were analyzed using Kruskal-Wallis and Dwass-Steel-Chritchlow-Fligner tests or ANOVA and Tukey test (α=0.05).

RESULTS

The 15% nanofibers showed antifungal activity (p < 0.05) and released Ce ions for 14 days. PMMA modified by 15% nanofibers did not show antifungal activity (p > 0.05) or release Ce ions. The nanofibers reduced the flexural strength and changed the color of the modified resin in proportions of 2.5% and 5% while decreasing its hardness in proportions of 0.5% and 5%. Regardless of the proportion, the nanofibers increased the PMMA contact angle (p < 0.05), without altering roughness and cytotoxicity of the acrylic resin (p > 0.05).

SIGNIFICANCE: The incorporation of PMMA-Ce nanofibers into PMMA resulted in no antifungal activity and affected the physical-mechanical properties of the modified material, without altering its cytotoxicity.