Comparison of the Marginal and Internal Fit of Ceramic Laminate Veneers Fabricated with Four Different CAM Techniques.

Purpose: Improvements in CAD/CAM have changed the methods of fabricating laminate veneers. The objective of this study was to evaluate the marginal and internal fit of ceramic veneers manufactured with different CAD/CAM techniques.

Materials and methods: A metal die was made by copying and scanning a prepared plastic maxillary right central incisor to design a laminate veneer. In total, 100 laminate veneers were made with four different CAD/CAM techniques (n = 25), including milled lithium disilicate (MLD), heat-pressed lithium disilicate (PLD) with 3D-printed wax patterns, milled zirconia (MZ), and 3D-printed zirconia (PZ). The virtual marginal and internal fit of fabricated veneers was evaluated with digital crown-fitting software. The actual marginal and internal fit was measured with the silicone replica method under a digital microscope. The measured data were analyzed using one-way ANOVA and Tukey tests.

Results: There were significant differences in marginal and internal fit (P < .001) among manufacturing techniques. Both the virtual and actual marginal and internal gaps were higher in the PLD and PZ groups compared to the MLD and MZ groups.

Conclusions: All four CAD/CAM techniques for manufacturing veneers-MLD, PLD with 3D printed wax patterns, MZ, and PZ-have clinically acceptable marginal and internal fit. MZ and MLD veneers demonstrated superior marginal and internal fit compared to PZ and PLD veneers with 3D-printed wax patterns.