Reduction of Candida albicans biofilm formation by coating polymethyl methacrylate denture bases with a photopolymerized film

Abstract

Statement of problemAs Candida albicans biofilm formation is associated with severe local and systemic infections in denture-wearing patients, its prevention or reduction becomes an essential factor in the health of this population. PurposeThe purpose of this in vitro study was to investigate whether 2 photopolymerized coatings of poly(acrylic acid) (PAA) and poly(itaconic acid) (PIA) can effectively reduce the adhesion of C albicans on denture base acrylic resin surfaces. Material and methodsThe surface of the polymethyl methacrylate (PMMA) denture base was modified through photopolymerization of a thin film of PAA or PIA. The polymeric coatings were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), contact angle goniometry (CA), and surface roughness measurement (Ra). For biological evaluation, the coated PMMA surfaces were tested in a C albicans biofilm dynamic formation model, observed by confocal laser scanning microscopy (CLSM), and quantified by the number of colony-forming units (CFUs). The cytotoxicity of the polymeric coatings was also evaluated by using a lactic dehydrogenase-based (LDH) test. For statistical analysis, ANOVA and the nonparametric Kruskal–Wallis test were used (α=.05). ResultsThe PMMA resin base surfaces coated with PAA and PIA had an inhibitory effect on C albicans growth, the wettability of the coated surface, and the average roughness. The PAA and PIA coatings had no statistically significant cytotoxic effect on periodontal ligament fibroblasts. ConclusionsPMMA acrylic resin base material was superficially modified through the incorporation of carboxylic acid groups by using PAA and PIA coatings that reduced the adherence of C albicans biofilm by 90%.