Ultra-Translucent Zirconia Laminate Veneers: The Influence of Restoration Thickness and Stump Tooth-Shade

Abstract

This in vitro study aimed to evaluate the final shade of translucent zirconia laminate veneers with varying thicknesses over teeth with different shades. Seventy-five chairside computer-aided design/computer-aided manufacturing (CAD/CAM) shade A1 third-generation zirconia dental veneers, with thicknesses of 0.50 mm, 0.75 mm, and 1.00 mm, were placed on resin composite teeth with shades ranging from A1 to A4. The laminate veneers were divided into groups based on thickness and background shade. All restorations were evaluated with a color imaging spectrophotometer, to map the veneer surface from A1 to D4. Regardless of the thickness or background shade, all dental veneers showed color alteration from the original shade. Veneers with 0.5 mm thickness tended to display the B1 shade, while veneers with 0.75 mm and 1.0 mm thickness primarily exhibited the B2 shade. The thickness of the laminate veneer and background shade significantly modified the original shade of the zirconia veneer. One-way analysis of variance was performed and a Kruskal–Wallis test was used to determine the significance between the three veneer thicknesses groups. The results indicated that the thinner restorations showed higher values with the color imaging spectrophotometer, suggesting that thinner veneers may result in more consistent color matching. This study underscores the importance of carefully considering thickness and background shade when selecting zirconia laminate veneers, to ensure optimal color matching and overall aesthetic outcomes.

Clinical Survival Rate and Laboratory Failure of Dental Veneers: A Narrative Literature Review

“…Frequently, fractures occur at the cervical onethird because the enamel is thinner, resulting in dentin exposure that may compromise longevity [8]. The causes of fractures in veneers are summarized in Table 1 [7,[9][10][11][12][13][14][15][16][17][18].…”

“…Improper veneer handling, especially for fragile feldspathic veneers. Incomplete polymerization using light-cure based resin cements for thick (>1 mm) opaque cement and opaque veneer (e.max MO *, HO *, zirconia) [16,17]. Inappropriate finishing and polishing, leading to cracks [18].…”

“…Debonding is another important complication documented in the literature; the causes of debonding are summarized in Table 2 [8,13,16,17,[28][29][30][31][32][33][34][35][36][37][38][39][40][41]. Debonding is related to the poor bond strength between the internal surface of the veneer and the resin cement, between the prepared tooth and the resin cement layer, or within the resin cement.…”

“…Incomplete polymerization using light-cure based resin cements for thick (>1 mm) opaque cement and opaque veneer (e.max MO *, HO *, zirconia) [16,17,41].…”

3D printing of ultra‐thin veneers made of lithium disilicate using the LCM method in a digital workflow: A feasibility study

“…The latter can be machined dry and thus enables very thin veneer thicknesses. 16,17 Lithium silicate ceramics, on the other hand, require wet grinding with diamond burs. This leads to a high machining effort and thus to a more expensive production and, in addition, necessitates a certain minimum layer thickness to ensure that the milling results are reliable.…”