title: Masking ability of bi- and tri- laminate all-ceramic veneers on tooth-colored ceramic discs.
abstract: A predictable esthetic outcome is imperative when placing ceramic veneers. Discolored teeth pose a major challenge as sufficient material thickness is required to achieve a good esthetic result. There is limited evidence in the literature that compares the masking ability of multi-laminate veneers.
  
  
  OBJECTIVE
  The aim of this in-vitro study was to compare the masking ability of bi-laminate (BL) and tri-laminate (TL) all-ceramic veneers cemented on tooth-colored ceramic discs.
  
  
  METHODS
  A total of 40 veneers (shade A1, 10-mm diameter, 0.8-mm thick) were manufactured-20 BL veneers (0.4-mm pressable ceramic coping veneered with 0.4-mm thick enamel layer) and 20 TL veneers (0.4-mm coping veneered with 0.2-mm thick opaque interlayer and 0.2-mm thick enamel layer). A bonding apparatus was utilized to adhesively cement all veneers on the ceramic discs (shade A1), simulating teeth of light and dark color. The resulting groups (N = 10 each) were the reference groups (shade A1 ceramic base) BL-1 and TL-1 veneers, and the test groups (shade A4 ceramic base) BL-4 and TL-4 veneers. The color of the cemented veneers was measured using a spectrophotometer. The data were converted to CIE L*a*b* coordinates, and ΔE* were calculated to allow for statistical analysis.
  
  
  RESULTS
  The color differences between the samples with the A1 and A4 ceramic bases were significantly lower when covered with TL veneers (mean ΔE*: 3.2 units) than with BL veneers (mean ΔE*: 4.0 units: p < 0.001), indicating a better masking ability of the TL veneers.
  
  
  CONCLUSIONS
  The 0.8-mm thick TL veneer was able to mask darker tooth-colored ceramic disc within clinically acceptable limits.
  
  
  CONCLUSIONS
  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.
authors: Department of Prosthetic Dentistry, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; dental Praxis, Kaltenkirchen, Germany.
authors: Daniel
authors: D
authors: Farhan
authors: Smitha
authors: S
authors: Sukumar
authors: Axel
authors: A
authors: von Stein-Lausnitz
authors: Ghazal
authors: G
authors: Aarabi
authors: Ahmad
authors: A
authors: Alawneh
authors: Daniel R
authors: DR
authors: Reissmann
mesh_terms: D002516:Ceramics; D003116:Color; D003801:Dental Veneers; D004955:Esthetics, Dental