Effect Of Two Kinds Of Dyeing Methods On Translucency Of High-translucent Zirconia

Objective:The purpose of this study was to compare the effects of two dyeing methods on the translucency of high-translucent zirconia ceramics using staining by immersion and pre-staining to dye the high-translucent zirconia ceramics,and to provide some reference for the dyeing technology,so as to obtain monolithic zirconia restoration with higher translucency and achieve better clinical aesthetic effect.Material and methods:1.Four kinds of high-translucent zirconia commonly used in clinic were selected.The white are ST(Upcera,China)and TT(Upcera,China),the pre-stained are ST-ML(Upcera,China)and TT-ML(Upcera,China).2.Cutting high-translucent zirconia into square flakes with edge Length 10mm and thickness 1mm by CAD/CAM Technology.The white zirconia were immersed as the immersion group,the pre-stained zirconia as the pre-staining group and the unstained zirconia as control group.The white zirconia were immersed in Upcera special staining solution and dyed as A2,B2 and C2 colors.The pre-stained zirconia were selected as A2,B2 and C2 colors.According to the color,the immersion group and the pre-staining group were divided into A,B and C subgroups,with 5 specimens in each group,a total of 70 specimens.3.After all specimens were dried and sintered,the chromological characteristic parameters(L~*、a~*、b~*)were measured under a standard black and white background using a Shade Eye NCC computer colorimeter(SHOFU,Japan)in the dark environment.Using Translucency parameter(TP)to evaluate the translucency.4.SPSS25.0 software was used for statistical analysis.According to the data characteristics,variance analysis,non-parametric test and multiple linear regression were used processing of these data,and the test level isα=0.05.Results:1.TP value of ST control group is 11.87±0.50;TP values of A2,B2 and C2colors in immersion group are 10.33±0.65,11.09±0.27,9.68±0.56;TP values of A2,B2 and C2 colors in pre-staining group are 10.46±0.55,11.21±0.54,9.49±0.96.TP value of TT control group is 12.93±0.73;TP values of A2,B2 and C2 colors in immersion group are 11.03±0.28,11.80±0.33,10.03±0.38;TP values of A2,B2 and C2 colors in pre-staining group are 11.17±0.35,11.94±0.39,10.16±0.40.2.Statistical description and analysis:(1)The effect of different dyeing methods on the TP value of high-translucent zirconia don’t have statistically significant difference(P>0.05);(2)The effect of different colors on the TP value of high-translucent zirconia have statistically significant difference(P<0.05);(3)There is no interaction among dyeing methods,brand and color on TP value of high-translucent zirconia.Conclusion:1.Dyeing can reduce translucency of high-translucent zirconia,but there is no significant difference between the two kinds of dyeing methods;2.Translucency of high-translucent zirconia is affected by different colors,and with the decrease of color lightness,the translucency decreases gradually,...