Effect of Low Nanodiamond Concentrations and Polymerization Techniques on Physical Properties and Antifungal Activities of Denture Base Resin

Abstract

Background: Denture base resin has some drawbacks. This study investigated the impact of nanodiamonds (ND) and autoclave polymerization on the surface characteristics, translucency, and Candida albicans adherence in polymethyl methacrylate (PMMA) denture base resin after thermocycling. Methods: Heat-polymerized PMMA discs (15 × 2 mm) with a total sample size n = 160 were studied. Specimens were categorized into two main groups (N = 80): conventional water-bath-polymerized PMMA (CP/PMMA) and autoclave-polymerized PMMA (AP/PMMA). Each group was subdivided according to the ND concentration into four groups (n = 20): unmodified PMMA as a control, and 0.1%, 0.25%, and 0.5% ND–PMMA. Scanning electron microscopy (SEM) was used to inspect the morphology of the ND and the ND–PMMA mixtures before heat polymerization. The specimens were exposed to thermal cycling (5000 cycles at 5 and 55 °C), then surface roughness was measured with a non-contact optical interferometric profilometer, contact angle with an automated goniometer, and translucency using a spectrophotometer. Colony-forming units (CFU) were used to determine the adherence of Candida albicans cells to the specimens. ANOVA and Tukey post hoc tests for pairwise comparison were utilized for the statistical analysis (α = 0.05). Results: Surface roughness was significantly reduced with ND addition to CP/PMMA (p ˂ 0.001), while the reduction was not statistically significant in AP/PMMA (p = 0.831). The addition of ND significantly reduced the contact angle, translucency, and Candida albicans count of CP/PMMA and AP/PMMA (p ˂ 0.001). The incorporation of ND in conjunction with autoclave polymerization of PMMA showed significant reduction in all tested properties (surface roughness, contact angle and Candida albicans adherence) except translucency (p = 0.726). Conclusions: ND addition to PMMA and autoclave polymerization improved the surface properties with respect to antifungal activities, while the translucency was adversely affected.

The efficacy of reinforcement of glass fibers and ZrO2 nanoparticles on the mechanical properties of autopolymerizing provisional restorations (PMMA)

“…Moreover, the nanoparticles fill the pores of the polymer matrix and improve the SR. These results agreed with the other studies ( Al-Harbi et al, 2018 , Fouda et al, 2021 , Abdulrazzaq and Al-Azzawi, 2022 , Mârt et al, 2022 ).…”

In Vitro Evaluation of Candida albicans Adhesion and Related Surface Properties of CAD/CAM Denture Base Resins

“…To remove nonadherent cells, the specimens were washed three times with phosphate buffer saline (PBS), then scraped and vortex for 2 minutes at 3,000 rpm to dislodge the adherent cells from the specimens. 22 23 24 To enumerate CFU count, 10-fold dilution in PBS was performed, before a volume of 100 µL was directly platted onto SDA plates and incubated at 30°C for 48 hours. The experiment was performed blindly in triplicates with positive and negative controls to ensure reproducibility.…”

The Antifungal and Antibiofilm Activities of Caffeine against Candida albicans on Polymethyl Methacrylate Denture Base Material

“…Nonadherent cells were removed by washing the discs twice with PBS and placed in new, sterile, 12-well plastic plates. Finally, the biofilms were scraped and vortexed for 2 min at 3000 rpm speed to dislodge the adherent cells from the denture [ 25 , 26 ]. The adherent fungal cells were evaluated by microplate reader (Bio-Rad xMark TM Microplate Spectrophotometer, Hercules, CA, USA) at 620 and 410 nm.…”