This study evaluated the marginal reproducibility of various all-ceramic crown fabrication systems using a wedge-shaped mold that mimics the crown margin. We utilized glass-ceramic blocks and high-strength composite resin blocks for CAD/CAM systems, heat-pressed and castable ceramics, with a 12% gold-silverpalladium alloy serving as a control. Each system produced a wedge-shaped specimen using a wedge-shaped brass mold. The thickness of the edge portion of the wedge was measured using the silicone replica technique, where thinner edges indicated better reproducibility. Data were analyzed using two-way ANOVA and Bonferroni analysis at a risk level of 5%. Ceramic and composite resin specimens made by CAD/CAM exhibited wavy edges, with significantly greater edge thickness than castable ceramic, heat-pressed ceramics, and the metal. Within the limitations of this study, the marginal reproducibility of CAD/CAM-made ceramics and composite resins was inferior to that of castable and heat-pressed ceramics.
Watanabe et al. (Sat,) studied this question.