Reduction in C.albicans Adhesion by SBMAm Co-polymer Coating on PMMA

Objectives: This study aimed to investigate denture-base-resin coatings prepared with a crosslinkable co-polymer containing sulfobetaine methacrylamide (SBMAm) and the relationship between their surface characteristics and the initial adhesion of Candida albicans (C. albicans).
Methods: Acrylic resin discs were coated with co-polymers containing various concentrations of SBMAm and N,N’-(4,7,10-trioxa-1,13-tridecadiamine) diacrylamide (JDA) as a crosslinking agent. Uncoated discs were used as controls. An acquired pellicle was formed on each disc using artificial saliva, and the discs were immersed in a suspension of C. albicans (JCM2085) cells. After incubation, tetrazolium salt (XTT-reduction) and colony forming unit (CFU) assays were performed and the morphogenesis of C. albicans was examined using scanning electron microscopy (SEM). The surface roughness, film thickness, and the water contact angle of each disc surface were measured. The durability test of the coating surface was evaluated by a brushing-abrasion machine.
Results: All coating groups showed significantly lower amounts of adhered C. albicans in the XTT-reduction and CFU assays compared with the control. SEM images confirmed lower adhesion of C. albicans on the coating surfaces than the control and many wrinkle structures were observed on the surfaces coated with co-polymers containing more than 30% SBMAm. There was no significant difference in surface roughness among all groups. The co-polymer films on the coated discs were less than 5.0 µm thickness, and these surfaces exhibited significantly lower mean water contact angles compared with the control. After the durability test, the water contact angle indicated higher mean values compared with before the test.
Conclusions: Crosslinkable co-polymers containing SBMAm can enhance the hydrophilicity of the surface of denture-base resins and reduce the initial adhesion of C. albicans.