Candida albicans Adhesion on 3D-Printed Denture Base Materials: An Exploratory Comparative In Vitro Study

Objective: This study aimed to quantitatively assess early adhesion and qualitatively assess 48-h biofilm-like morphology of Candida albicans (C. albicans) on seven commercially available 3D-printed denture base resins compared with conventional heat-polymerized polymethyl methacrylate (PMMA). Materials and Methods: A total of 128 disc-shaped specimens (n = 16 per material) were fabricated using seven 3D-printed denture base resins and a PMMA control. Early C. albicans adhesion was quantitatively evaluated using the XTT assay at 490 nm after a fixed 1-h incubation. Qualitative analysis was performed using field-emission scanning electron microscopy (FESEM) at 1.5 h (early adhesion) and 48 h (biofilm-like morphology) on two representative printed resins (selected based on the lowest and highest XTT values among printed materials), PMMA, and a negative control. Results: XTT analysis demonstrated significantly higher early adhesion of C. albicans on all 3D-printed denture base resins compared with PMMA (p < 0.001). Among the printed resins, Shining 3D demonstrated significantly higher XTT values than all other printed resins except PRIZMA (p < 0.05). PRIZMA showed significantly higher adhesion than DETAX, NextDent, and ASIGA (p < 0.05). FESEM images at 1.5 h showed early yeast attachment on the two representative printed resins, while 48-h images showed visible surface colonization with yeast and hyphal forms on these representative printed resins compared with sparse yeast attachment on PMMA. Conclusions: Within the limitations of this in vitro study, 3D-printed denture base resins exhibited significantly greater early C. albicans adhesion than conventional PMMA. Among the printed resins, Shining 3D and PRIZMA showed the highest early adhesion. Qualitative SEM of two representative printed resins suggested visible surface colonization at 48 h. Because mature biofilm was not quantified and only two printed materials were imaged, these findings should be considered preliminary. Further studies are needed to confirm biofilm development and to determine the role of material chemistry, surface properties, and printing parameters.