Antifungal Effect of Poly(methyl methacrylate) Coated with Polyelectrolyte Multilayers

Due to teeth loss, a large proportion of the elderly rely on full or partial dentures for esthetic, speaking, and eating reasons. A variety of polymers are used in the production of removable prostheses, with poly-(methyl methacrylate) (PMMA) being a widely used material for making denture bases. However, underdenture stomatitis caused by the fungi Candida albicans is still an open problem. The purpose of this work was to consider the impact of polyelectrolyte multilayer (PEM) coating on PMMA surfaces and the effect of the addition of sucrose on the adhesion properties of C. albicans. Two polyelectrolytes were applied for the formation of the PEM coating: poly-(allylamine) hydrochloride (PAH) and poly-(acrylic) acid (PAA). The uncoated and coated surfaces were characterized in terms of topography, surface potential, and hydrophobicity. The extent of adhesion of C. albicans to the surfaces was assessed by scanning electron microscopy. Results show that surfaces coated with negatively charged PAA as the PEM terminating layer adhere less C. albicans than uncoated PMMA or surfaces coated with positively charged PAH as the PEM terminating layer. The addition of sucrose increases the fungal adhesion extent of C. albicans to both types of coated surfaces, lowering the PAA antiadhesion properties. With the addition of sucrose, we were trying to mimic the impact of dentures on patients with a sugar-rich diet.