In vitro evaluation of artificial ageing on surface properties and early Candida albicans adhesion to prosthetic resins

Objective The aim of this in vitro study was to examine potential changes and influences of prosthetic resin surface properties on Candida albicans adhesion after surface treatment or artificial ageing. Materials and methods Standardized specimens of a denture base resin and a veneering composite were prepared, polished, and randomly subjected to different surface roughness treatments or artificial ageing protocols (storage in ethanol or artificial saliva for 7/90 d, thermocycling). Surface roughness (Ra) and surface free energy were determined prior and after each treatment. Specimens were incubated with phosphate buffered saline or whole saliva for 2 h at 37A degrees C, and later with Candida albicans suspension (2.5 h, 37A degrees C). Adherent viable fungi were quantified using a bioluminescence assay. Results Artifical ageing did not affect substratum surface roughness, yet slight increases in substratum surface free energy and significant increases in Candida albicans adhesion were observed. Saliva coating marginally influenced Candida albicans adherence to reference and surface treated specimens, yet more pronounced differences in Candida albicans adhesion between the various artificially aged specimens were found. Conclusion No correlation between substratum surface roughness or surface free energy and Candida albicans adhesion could be established.