Influence of the color of composite resin foundation and luting cement on the final color of lithium disilicate ceramic systems.
BACKGROUND
Lithium disilicate restorations are commonly used, particularly in the anterior region. The color of the underlying composite resin foundation (CRF) and luting cement may negatively affect the color of lithium disilicate ceramic restorations.


OBJECTIVE
The purpose of this in vitro study was to investigate the effect of CRF and resin cement materials on the color of lithium disilicate ceramics in 2 different translucencies.


METHODS
Twenty disks (11×1.5 mm, shade A2) were fabricated from medium-opacity (mo) (n=10) and high-translucency (ht) (n=10) lithium disilicate (Lds) blocks (IPS e.max Press). Five CRF disks (11×3 mm) were fabricated in 5 different shades (A1, A2, A3, B2, C2) and 30 resin cement disks (11×0.2 mm) in the shades of translucent (Tr), universal (Un=A2), and white-opaque (Wo). Ceramic specimens were placed on each CRF, and the resin cement combination and color was measured with a spectrophotometer. CIELAB color coordinates were recorded, and the color coordinates of both ceramics on the shades of the A2 CRF and resin cement were saved as the control. Color differences (ΔE00) between the control and test groups were calculated. Data were analyzed with 3-way analysis ANOVA and compared with the Tukey HSD test (α=.05).


RESULTS
The ΔE00values were influenced by the shades of the CRF, resin cement materials, and also their interactions (P<.05). The ΔE00values were not affected by the ceramic type. The ΔE00values of the Wo cement groups (1.73 to 2.96) were significantly higher than those of the other cement shades (0.88 to 1.29) for each ceramic type and CRF shade (P<.05).


CONCLUSIONS
Lithium disilicate ceramics in 2 different translucencies were similarly influenced by the color of the underlying cement and CRF. When translucent and universal cement shades were used, the core shade did not affect the final color of the ceramics. White opaque cement caused clinically unacceptable color changes in both ceramics on all shades of CRFs except the C2 CRF and when high translucency ceramic was used on the A2 CRF. These changes were clinically acceptable, but perceptible.
Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Ordu University, Ordu, Turkey.
Doğu Ömür
DÖ
Dede
Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Bülent Ecevit University, Zonguldak, Turkey.
Onur
O
Sahin
Practitioner, Samsun Public Oral Health Center, Samsun, Turkey.
Oğuz Süleyman
OS
Özdemir
Associate Professor, Division of Restorative Science and Prosthodontics, The Ohio State University, College of Dentistry, Columbus, Ohio. Electronic address: yilmaz.16@osu.edu.
Burak
B
Yilmaz
Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Ordu University, Ordu, Turkey.
Ersan
E
Celik
Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Bülent Ecevit University, Zonguldak, Turkey.
AySegül
A
Köroğlu
D002516:Ceramics / Q000627:therapeutic use*; D003188:Composite Resins / Q000627:therapeutic use*; D003738:Dental Cements / Q000627:therapeutic use*; D003776:Dental Porcelain / Q000627:therapeutic use*; D017266:Dental Prosthesis / Q000379:methods; D003793:Dental Restoration, Permanent / Q000379:methods; D004955:Esthetics, Dental; D006801:Humans; D017797:Prosthesis Coloring / Q000379:methods
D003188:Composite Resins; D003738:Dental Cements; C493120:lithia disilicate; D003776:Dental Porcelain