Masking Ability of Bi‐ and Tri‐ Laminate All‐Ceramic Veneers on Tooth‐Colored Ceramic Discs

Abstract

Increased understanding of the masking ability of ceramics and of color science is necessary in these esthetically aware times. Providing tri-laminate veneers for darker colored teeth seems to result in more predictable esthetical results than when using bi-laminate veneers. Patients with discolored/darker teeth may benefit from a more predictable esthetic result when teeth restored with tri-laminate rather than bi-laminate veneers.

The Effect of Luting Cement and Titanium Base on the Final Color of Zirconium Oxide Core Material

“…Good color match usually results in superb esthetics of the restoration. Undesirable color differences between the neighboring natural teeth and the fixed prostheses are dependent on the variations in ceramic materials used, as well as the metallic or zirconia core material . Translucency can be described as a state between complete opacity and transparency .…”

“…The masking ability of a zirconia ceramic restoration is measured by the color difference (ΔE*) when placed over different backgrounds . The system, called CIELab*, expresses color by numbers and calculates the differences between two colors in a way that corresponds to visual perception.…”

“…In this system, the benchmark for scientific purposes, color is expressed by three coordinates: L* value is the degree of lightness of an object, a* value is the degree of redness/greenness, and b* value is the degree of yellowness/blueness. In the CIELab* system, a formula is used to calculate color differences: …”

“…Two factors need to be considered when establishing clinical guidelines for ΔE*: perceptibility (detection of the difference in color between two objects by the human eye) and acceptability (color difference in shade match acceptable to the human eye) . As Farhan et al noted, “Because the identification of a ΔE* unit for the visual perception of color difference is a difficult task, there are no well‐established values for perceptibility and clinical acceptability for color matching between ceramic restorations and natural teeth. Studies provide a range of values for acceptability thresholds: 2.25, 2.6, 3.3, and 3.7 ΔE as a visually acceptable match between the restoration and [natural teeth].” Whether there is actually a difference between perceptibility and acceptability, however, is a topic that has not been clearly identified .…”

“…Undesirable color differences between the neighboring natural teeth and the fixed prostheses are dependent on the variations in ceramic materials used, as well as the metallic or zirconia core material. 1,[5][6][7][8][9] Translucency can be described as a state between complete opacity and transparency. 1,10,11 Although full ceramics are transparent, metallic ceramics do not have this property.…”