Evaluation of optical, surface, and microbiological properties of computer-aided design/computer-aided manufacturing-milled and three-dimensional-printed denture bases after aging by thermocycling: An in vitro study.

Aim: The purpose of this study was to evaluate the surface properties, optical stability, and Candida albicans adhesion to resins used in the base of conventional, milled, and three-dimensional (3D)-printed dentures after aging by thermocycling.

Settings and design: In vitro study.

Materials and methods: A total of 96 resin samples were manufactured, divided into 3 resin groups (n= 32) (conventional thermally activated, milled and 3D-printed), and subdivided into 4 aging times by thermocycling at temperatures 5 ± 1°C and 55 ± 1°C in 24h, 5.000, 10.000, 20.000 cycles (n = 8), evaluating the adhesion of C. albicans, optical stability, surface roughness, hydrophilicity, and energy surface.

Statistical analysis used: Data were evaluated by two-way ANOVA and Tukey's test for pairwise comparisons (P < .05).

Results: Conventional resin exhibited lower C. albicans colonization, with significant reductions at T1 (1.05±1.38) (P = .003) and T3 (3.67 ±1.86) (P = .023) compared to other resins. The conventional resin had significantly the lowest ΔE00 value at T0 (0.98 ± 0.41) (P < .05). The milled resin had significantly lower roughness value at T0 (0.031 ± 0.00) (P < .05). The conventional resin had significantly higher surface energy values compared to the other resins (P < .05). The conventional resin exhibited a significantly lower water contact angle than the other resins (P < .001).

Conclusion: The conventional thermally activated resin showed less adhesion of C. albicans than the resins manufactured by CAD/CAM. Among CAD/CAM resins, milled resin showed better properties than 3D-printed resin over time.