Effectiveness of Combination of Dentin and Enamel Layers on the Masking Ability of Porcelain

Abstract

This study evaluated the masking ability of different porcelain thicknesses and combination of enamel and/or dentin porcelain layers over simulated background dental substrates with higher (A2) and lower (C4) color values. Combination of the enamel (E) and dentin (D) monolayer porcelain disks with different thicknesses (0.5 mm, 0.8 mm, and 1 mm) resulted in the following bilayer groups (n=10): D1E1, D1E0.8; D1E0.5; D0.8E0.8; D0.8E0.5, and D0.5E0.5. CIELAB color coordinates were measured with a spectrophotometer. The translucency parameter of mono and bilayer specimens and the masking ability estimated by color variation (ΔE*ab) of bilayer specimens over simulated dental substrates were evaluated. Linear regression analysis was used to investigate the relationships translucency parameter × ΔE*, translucency parameter × porcelain thickness, and ΔE* × porcelain thickness. Data were analyzed statistically (α= 0.05). Thinner porcelain disks were associated with higher translucency. Porcelain monolayers were considerably more translucent than bilayers (enamel + dentin). Dentin porcelain was less translucent than enamel porcelain with same thickness. ΔE* was always lower when measured over A2 background. Higher ΔE* was observed for the C4 background, indicating poorer masking ability. Increased ΔE* was significantly associated with increased translucency for both backgrounds. Decreased translucency and ΔE* were associated with increased total porcelain thickness or increased dentin thickness for both backgrounds. In conclusion, increased porcelain thickness (particularly increased dentin layer) and increased porcelain opacity resulted in better masking ability of the dental backgrounds.

Inorganic filler content of resin-based luting agents and the color of ceramic veneers

“…Since the color of thin CLV can be affected by several factors and achieving natural tooth-like restoration is still one of the greatest challenges for restorative dentistry, 8,10,27,28,29,30 this study evaluated the influence of low, intermediate, and high barium borosilicate inorganic filler content (55%, 65%, and 75% of mass fraction, respectively) of experimental resin luting agent on the translucency parameter (TP), color change (∆E 00 ), and CIEL*a*b* individual color coordinates of simulated CLVs. The hypotheses tested were that the higher inorganic filler content had a larger effect on the optical properties (∆E 00 and TP) of simulated CLV.…”

Shade of Resin‐Based Luting Agents and Final Color of Porcelain Veneers

“…In contrast, over A2 dental substrate, higher color differences might be expected. Nonetheless, case‐by‐case evaluation should be made, since the final optical appearance of porcelain veneer restorations is sensitive to multiple factors, such as production/processing parameters controlled by the dental‐lab technician and a wide range of particularities of each patient and even further, each tooth (e.g., luminosity, shape, and texture). Finally, further studies are recommended to evaluate the effect of aging on the color of porcelain veneers cemented by different shades of resin‐based luting agents to distinct backgrounds.…”

Masking ability of bleach‐shade resin composites using the multilayering technique

“…A ceramic 0 M1 opaque shade disc (Vita VM9, Vita Zahnfabrik, Bad Säckingen, Germany) was also produced to simulate a bleached tooth surface, and was used as a standard reference to calculate the color difference. The dimensions of the substrates were 2.0 mm thick and 11.0 mm in diameter 28‐30 . The schematic representation of the experimental design is showed in Figure 1.…”