Evaluation of Different Thickness, Die Color, and Resin Cement Shade for Veneers of Multilayered CAD/CAM Blocks.
OBJECTIVE
To investigate the effect of resin cement color on the post-cementation shade of thin laminate veneers milled from multilayered glass ceramic blocks for each layer.


METHODS
Thin slices (N = 180) with two thicknesses (A: 8 × 8×0.55 mm and B: 8×8×0.8 mm; n = 90/group) were obtained from multilayered glass ceramic blocks using a diamond saw. Resin die specimens were prepared (8 × 8 × 4 mm) (n = 180) and divided into two resin cement colors (D: -3. L: +3) and one control group (C: translucent). Each slice was luted to the composite specimens using a dual-curing resin cement under a constant load of 250 g and light-polymerized for 120 seconds. Specimens were placed on a white background and CIELab values for each layer of the blank slices (incisal [In], body [Bo], and cervical [Ce]) were recorded using a dental contact spectrophotometer. The values were calculated as ΔE, and the data were statistically analyzed (one-way ANOVA, Shapiro-Wilk).


RESULTS
Mean ΔE values for A and B were significant (p < 0.05) for In (A: 6.2 ± 1.1; B: 6.6 ± 1.2), Bo (A: 5.1 ± 2.6; B: 3.9 ± 1), and Ce (A: 5.3 ± 2.7; B: 3.8 ± 1.2). Mean ΔE values for In for D and L for A and B groups were significantly higher (6.3 ± 1.2; 6.6 ± 1.2) than Bo and Ce for D (4.4 ± 2.4; 4.6 ± 2.6) and L (4.6 ± 1.4; 4.5 ± 1.7) groups (p < 0.05), respectively. Mean differences between Bo and Ce for A and B groups were insignificant (p ≥ 0.05), while for In the differences were significant. Mean differences between Bo and Ce for A (5.1 ± 2.6; 5.3 ± 2.7) and for B (3.9 ± 1; 3.5 ± 1.2) groups were insignificant (p ≥ 0.05), while for In the differences were significant (6.2 ± 1.1 for A and 6.6 ± 1.2 for B).


CONCLUSIONS
The color changes for body and cervical regions of multilayered ceramic veneers were not affected by resin color or ceramic thickness, but the incisal area was affected. The translucency of each layer in ceramic veneer fabricated with multilayered blanks should be considered for clinical situations.
Department of Prosthodontics, School of Dentistry, Ege University, Izmir, Turkey.
Muharrem Erhan
ME
Çömlekoğlu
Department of Prosthodontics, School of Dentistry, Ege University, Izmir, Turkey. dt.gamzeozturk@gmail.com.
Gamze
G
Paken
Department of Prosthodontics, School of Dentistry, Ege University, Izmir, Turkey.
Firuzan
F
Tan
Department of Prosthodontics, School of Dentistry, Ege University, Izmir, Turkey.
Mine
M
Dündar-Çömlekoğlu
University of Zürich, Dental Materials Unit, Center for Dental and Oral Medicine, Clinic for Fixed and Removable Prosthodontics and Dental Materials Science, Zürich, Switzerland.
Mutlu
M
Özcan
Department of Prosthodontics, School of Dentistry, İzmir Katip Çelebi University, Izmir, Turkey.
Ender
E
Akan
Department of Prosthodontics, School of Dentistry, Ege University, Izmir, Turkey.
Akın
A
Aladağ
D002484:Cementation; D003116:Color; D017076:Computer-Aided Design; D003776:Dental Porcelain; D003801:Dental Veneers; D006801:Humans; D008422:Materials Testing; D019279:Resin Cements
D019279:Resin Cements; D003776:Dental Porcelain
Dental spectrophotometer; color; multilayered CAD/CAM blocks; resin cement