Abstract
Objectives: Early adhesion is the first step leading to the colonization of the biomaterials which may lead to the biodeterioration of the materials. The aim of this study was to evaluate the in vitro adhesion of clinical isolates of Candida albicans to polysiloxane soft liners or denture base resin.
Methods: Two clinical isolates of Candida albicans collected from the polysiloxane soft liners used for 1 year and a reference strain (CCGUG19915, Culture collection of the University of Gothenburg) were chosen for the experiments. Polysiloxane soft liners Molloplast B, GC Reline soft, and denture base polymer Palapress Vario were used. Specimens of each material were prepared against a glass surface. The specimens (5 ×5 ×3 mm). were immersed in Simulated Body Fluid (SBF) for 24 h and either coated with filter-sterilized stimulated whole saliva at room temperature for one hour or used without saliva coating. Then the specimens were rolled in a tube containing Candida cells with an optical density of A660~1.0 for one hour. The in vitro retention of Candida albicans were assesed by microscopic (SEM) counting and conventional culturing methods. For culturing method, microbrushes were used for harvesting adhered cells. The yeast adhesion results were analyzed with three-way factorial analysis of variance (ANOVA) and Tukeys post hoc.
Results: There was a significant decrease in the number of cells attached in vitro to saliva-coated surfaces compared to non-treated surfaces (p<.05). One of the clinical isolates adhered in significantly higher numbers to the non-treated surfaces(p<.05), but after saliva coating the adhesion was lower and comparable to other strains(p>.05). Conclusions: Saliva coating reduced the initial adhesion of yeasts to liners in vitro and minimized the differences between strains. This may indicate that a decreased saliva flow or quality may be a predisposing factor for colonisation.