Comparison of surface integrity, longevity of posterior tooth-colored crowns fabricated by conventional, CAD/CAM, and 3D printing techniques
TL;DR
Material type and fabrication workflow significantly influenced internal and marginal surface roughness of posterior tooth-colored crowns and the crowns survival rates were more closely associated with material type than fabrication method.
Abstract
Introduction This in vitro study evaluated internal and marginal surface roughness and simulated thermocycling survival of posterior tooth-colored crowns fabricated using conventional laboratory, CAD/CAM milling, and digital light processing 3D printing workflows. Methods The roughness analysis included 46 crowns allocated to six groups: lab-made crowns (n = 6), IPS e.max CAD (n = 8), IPS Empress CAD (n = 8), Lava Ultimate (n = 8), IPS e.max ZirCAD (n = 8), and 3 D SprintRay Ceramic (n = 8). Internal and marginal arithmetic mean roughness (Ra, µm) were measured with a 3D non-contact profilometer. Because residual normality and variance homogeneity assumptions were not satisfied, group differences were analyzed using Kruskal–Wallis tests followed by Holm-adjusted pairwise Mann–Whitney U tests. Results Internal Ra differed significantly among groups (H = 25.76, df = 5, p < 0.001). 3D printed SprintRay Ceramic showed the highest internal Ra (29.27 ± 5.45 µm) and was significantly rougher internally than every other group after Holm correction. Marginal Ra also differed significantly among groups (H = 41.86, df = 5, p < 0.001). IPS e.max CAD showed the highest marginal Ra (26.81 ± 1.73 µm), followed by lab-made crowns (19.31 ± 6.40 µm), whereas IPS e.max ZirCAD showed the lowest marginal Ra (4.82 ± 1.03 µm). Conclusion Within the limitation of the present study material type and fabrication workflow significantly influenced internal and marginal surface roughness of posterior tooth-colored crowns. The crowns survival rates were more closely associated with material type than fabrication method.