We have located links that may give you full text access.
Effect of Thickness of Zirconia Ceramic on Its Masking Ability: An In Vitro Study.
Journal of Prosthodontics : Official Journal of the American College of Prosthodontists 2017 April 29
PURPOSE: Color-masking ability of zirconia ceramics as coping materials has not been clearly understood in zirconia-based restorations. This in vitro study aimed to evaluate the effect of zirconia ceramic thickness on its masking ability, and to define a thickness cutoff for the tested ceramic.
MATERIALS AND METHODS: Ninety zirconia disc specimens, in nine thickness groups including 0.4, 0.6, 0.8, 1, 1.2, 1.4, 1.6, 1.8, and 2 mm were fabricated. A white substrate and a black substrate were prepared. The disc specimens were placed onto the substrates for spectrophotometric measurements. A spectrophotometer measured L(*) , a(*) , and b(*) color attributes for the specimens. ΔE value was calculated to determine the color difference of specimens on the white and black substrate. Then the ΔE values were compared with an acceptable clinical threshold (ΔE = 5.5) and an ideal threshold (ΔE = 2.6). Welch test, Games-Howell Post Hoc, one-sample t-test, and a regression analysis were performed (p < 0.05).
RESULTS: The means of ΔE values for the thickness groups of 0.4, 0.6, 0.8, 1, 1.2, 1.4, 1.6, 1.8, and 2 mm were 13.0, 11.9, 9.7, 5.0, 4.2, 3.9, 2.2, 1.9, and 1.5, respectively. A significant difference was found in the ΔE value among the groups (p < 0.0001). An exponential relation was detected between the thickness and the ΔE by the regression analysis (∆E = 25.68e(-1.45 (thickness)) ).
CONCLUSIONS: The masking ability increased as the zirconia ceramic thickness increased. The tested zirconia ceramic had an acceptable clinical masking ability with a minimum thickness of 1 mm, and an ideal masking ability with a minimum thickness of 1.6 mm.
MATERIALS AND METHODS: Ninety zirconia disc specimens, in nine thickness groups including 0.4, 0.6, 0.8, 1, 1.2, 1.4, 1.6, 1.8, and 2 mm were fabricated. A white substrate and a black substrate were prepared. The disc specimens were placed onto the substrates for spectrophotometric measurements. A spectrophotometer measured L(*) , a(*) , and b(*) color attributes for the specimens. ΔE value was calculated to determine the color difference of specimens on the white and black substrate. Then the ΔE values were compared with an acceptable clinical threshold (ΔE = 5.5) and an ideal threshold (ΔE = 2.6). Welch test, Games-Howell Post Hoc, one-sample t-test, and a regression analysis were performed (p < 0.05).
RESULTS: The means of ΔE values for the thickness groups of 0.4, 0.6, 0.8, 1, 1.2, 1.4, 1.6, 1.8, and 2 mm were 13.0, 11.9, 9.7, 5.0, 4.2, 3.9, 2.2, 1.9, and 1.5, respectively. A significant difference was found in the ΔE value among the groups (p < 0.0001). An exponential relation was detected between the thickness and the ΔE by the regression analysis (∆E = 25.68e(-1.45 (thickness)) ).
CONCLUSIONS: The masking ability increased as the zirconia ceramic thickness increased. The tested zirconia ceramic had an acceptable clinical masking ability with a minimum thickness of 1 mm, and an ideal masking ability with a minimum thickness of 1.6 mm.
Full text links
Related Resources
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app