Comparison of surface integrity, longevity of posterior tooth-colored crowns fabricated by conventional, CAD/CAM, and...

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.

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.

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).

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.