Evaluation of Surface Roughness and Wear Resistance of Additively and Subtractively Manufactured CAD-CAM Dental Materials: An In Vitro Study.

Abstract

Purpose: To evaluate the wear resistance and surface roughness of subtractively manufactured resin matrix ceramics and additively manufactured hybrid composites, both subjected to different surface treatments and thermomechanical aging.

Materials and methods: Two additively manufactured materials and one subtractively manufactured polymer-infiltrated resin ceramic were used to fabricate square-shaped specimens.These specimens were divided into two subgroups based on surface treatment (n = 12). After surface roughness measurements and SEM analysis, the specimens were subjected to thermomechanical aging. Pre- and post-aging scans were analyzed to calculate wear depth. Surface roughness and SEM analyses were repeated, and 2-way ANOVA with Tukey's HSD test was used for statistical analysis.

Results: Glazed surfaces exhibited significantly higher wear depth than polished ones (p = .018). Vita Enamic showed significantly greater wear depth compared to both VarseoSmile Crown Plus (p = 0.002) and P-Crown V2 (p = 0.001). For polished surfaces, Vita Enamic had significantly greater wear depth than VarseoSmile Crown. Plus (p = 0.001) and P-Crown V2 (p < .05). Initially, surface roughness values for glazed surfaces were similar (p = .076), but aging increased roughness significantly, with glazed P Crown V2 being rougher than glazed VarseoSmile Crown Plus (p = .001). After aging, glazed surfaces had significantly higher surface roughness than polished ones across all materials.

Conclusion: Material type and surface treatment affected surface roughness and wear depth during thermomechanical aging. Glazed surfaces showed higher wear depth and roughness, with the glaze layer removed after aging. Polished surfaces exhibited greater wear for subtractive materials.