Effect of veneering technologies on color and translucency of Y2O3 stabilized tetragonal zirconia polycrystals all-ceramic restorations
10.3321/j.issn:1002-0098.2008.03.014
- VernacularTitle:饰瓷工艺对氧化锆陶瓷颜色和透光性的影响
- Author:
Lei ZHANG
1
;
Xiao-Ping LUO
;
Yu-Juan SHI
Author Information
1. 南京大学医学院附属口腔医院
- Keywords:
Dental porcelain;
Zirconia;
Veneering technology;
Color parameters
- From:
Chinese Journal of Stomatology
2008;43(3):178-181
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare color parameters and transmittance of Y2O3 stabilized tetragonal zirconia polycrystals(Y-TZP)all-ceramic restorations using different veneering technologies.Methods Fifteen disc specimens with 10 mm in diameter and(0.50±0.01)mm in thickness were fabricated of IPS e.max ZirCAD core material,and ZL1 IPS e.max ZirLiner was layered in 0.10 mm thickness.The specimens were divided into three groups randomly(n=5 per group).Group ZP was veneered 0.60 mm by heat-pressing;group ZC was veneered 0.60 mm by layering;group ZPC was veneered 0.30 mm by heatpressing and then 0.30 mm by layering.Color parameters L*,a*,b*and transmittance of zirconia specimens were measured before and after veneering with ShadeEye NCC dental chromameter and spectrophotometer.Color saturation C*ab and color difference ΔE were calculated in the following formulae:C*ab=[(a*)2+(b*)2]1/2,ΔE=[(△L*)2+(△a+)2+(△b*)2]1/2.One-way analysis of variance and Turkey's multiple comparison test were used to analyze data(α=0.05)by SPSS 10.0 statistic software.Color parameters of A2 shade tabs were measured,and color differences between each group and tab were calculated.Results As to ZP、ZPC、ZC groups,the value of a*increased(-1.35±0.07,-0.64±0.06,-0.36±0.05)(P＜0.05),the value of b*decreased(27.01±0.07,25.48±0.11,23.28±0.25)(P＜0.05),and the value of C*ab decreased(27.04±0.08,25.49±0.11,23.28±0.25)(P＜0.05).L*and transmittance were maximum in ZP group(87.53±0.48,1.64±0.03)and minimum in ZPC group(82.14±0.18,1.47±0.01)(P＜0.05).Compared with standard A2 shade tab,the color difference of ZC group was minimum(ΔE=1.04),and the color difference of ZP group was maximum (ΔE=4.86).Conclusions Y-TZP all-ceramic restoration veneered by heat-pressing was the most transparent and lightest;while veneered by both heat-pressing and layering,the restoration was worst in translucency and the least light.The color of zirconia all-ceramic restoration veneered by layering was the most similar to standard shade tab,and the color difference was minimum.
