Effect Of Printing Parameters On Surface Roughness And Candida Adherence

This study investigates the influence of build orientation, layer thickness, and support structures on the surface roughness of 3D-printed flexible denture resins and their effect on Candida adherence. 3D-printed denture materials were fabricated using Digital Light Processing (DLP): two flexible resins (Graphy Resin TFDH, 3Dresyn OD FDB 3D) and one rigid base material (Graphy Resin THD). Specimens were printed with varying parameters, including build orientations (30°, 40°, 45°), layer thicknesses (50µm, 100µm), and support structures (partial, full). Disc-shaped specimens (15×2mm) were produced for each parameter combination, with a control group of heat-cured denture base (HUGE Dental, Shadong). Surface roughness was measured using a profilometer, and Candida adherence was assessed via the crystal violet assay. Statistical analysis was performed using ANOVA, post hoc testing, and Pearson’s correlation for surface roughness and Candida adherence. Surface roughness increased with higher build orientations (45°) (M= 5.328±2.323) and thicker layers (100 µm) (M= 5.343±2.6). These factors correlated with higher absorbance values with negative reduction in adherence (M= -53.137±99.355 and M= -35.747±89.953, respectively, p<0.05). The unpolished surfaces of Graphy Resin TFDH and 3Dresyn OD FDB 3D exhibited greater roughness, suggesting an increased potential for adherence. Build orientation and layer thickness significantly affect surface roughness and Candida adherence of 3D-printed flexible denture resins. Optimizing printing parameters can reduce microbial colonization and improve denture hygiene and clinical outcomes.