Effect of denture-coating composite on Candida albicans biofilm and surface degradation after disinfection protocol

Introduction Denture stomatitis is the most common pathology affecting denture wearers and its main cause is colonisation of dentures with Candida albicans. Objective This study investigated the effectiveness of two commercial composite surface sealants (Biscover® LV and Surface Coat®) to reduce C. albicans biofilm colonisation on denture resin, as well as their surface integrity after disinfection cycles with 1% sodium hypochlorite solution. Methods Heat-cured acrylic resin specimens were manufactured (10 mm × 10 mm × 1 mm). The specimen surfaces were mechanically polished to simulate rough or smooth denture surfaces. Four surface-treatment groups were tested: smooth surfaces [0.3 μm of mean roughness (Ra)]; rough surfaces (3 μm of Ra); rough surfaces treated with Biscover® LV; and rough surfaces treated with Surface Coat®. Specimens of each group were randomly divided to undergo immersion in distilled water or 1% sodium hypochlorite for 30 or 90 cycles each. Specimens of all groups in each immersion solution were tested using a crystal violet (CV) staining assay for biofilm quantification and by scanning electron microscopy for visual analyses of surface integrity and biofilm structure. CV assay data were analysed using one-way analysis of variance (ANOVA) followed by Tukey's multiple comparison test (P < 0.05). Results The effectiveness and surface integrity of Biscover® LV-treated surfaces were similar to those of smooth surfaces, whereas Surface Coat®-treated surfaces presented a similar performance to rough surfaces in all solutions and cycles. Conclusion These results suggest the possibility of clinical use of Biscover® LV for denture coating on surfaces in which mechanical polish is not indicated, such as the fitting surface.