Effect Of Different Surface Treatment Methods On Bonding Performance Of Zirconia Substrate And Veneer Ceramic

Objective:To compare different surface processing way on bonding properties of zirconia base-porcelain veneer layer porcelain, through the shear strength testing experiment, scanning electron microscope (SEM) and the interface micro structure analyze by spectrum analysis, to improving the success rate of zirconia all ceramic restorations provide a theoretical basis.Methods:The Sirona zirconia core material was cut and sintered into 44 rectangular specimens (10 mm x 5 mm x 5 mm).The specimens were randomly divided into four groups(n=11).Treatment methods are as follows:the experimental group of 1:after the crystallization of the substrate to do blasting treatment, and then sintering veneering porcelain;the experimental group of 2:after the crystallization of the substrate, first to do nano zirconia coating sintering, and then sintering veneering porcelain;the experimental group of 3:after the crystallization of the substrate, first to do blasting treatment, and then do nano zirconia coating sintering, the final sintering veneering porcelain;the control group:after the crystallization of the base of the direct sintering porcelain.Above each substrate ceramic materials are used in slip casting sintering of 5mm x 5mm x 5mm thick veneering porcelain.10 specimens of each group were selected to measure the shear strength in an electronic universal dynamometer.Each group randomly selected 1 basal porcelain and double porcelain specimens, the spectrum analysis method using scanning electron microscope, observing the microstructure interface, combined with the situation between zirconia and veneering porcelain of porcelain base.Results:1. The shear bonding strength test resultsThe shear strength measured in the experimental group 1 was 17.96±0.31 MPa; the shear strength measured in the experimental group 2 was was 20.14±0.68 MPa;the shear strength measured in the experimental group 3 was 24.65±0.67 MPa;the shear strength measured in the control group was 14.06±0.44 MPa.There were statistically significant differences between the groups (P< 0.01).2. The scanning electron microscopy (SEM) observationsIn the experimental group of 1, the surface of the zirconia samples showed a uniform rough surface, which showed irregular concave convex, and the combination of the two layers of porcelain have obvious mosaic.In the experimental group 2, the surface of the zirconia test piece is clear shallow concave and ridge, the shape is more regular, the sol has no crack, no gap. The combination of the two layers of porcelain was flat, and the combination was close.In the experimental group of 3, the surface of the zirconia samples showed a uniform rough surface, visible irregular concave convex, no cracks, no cracks, and the combination of the two layers of porcelain have obvious mosaic.In the control group, the surface of the zirconia samples formed clear grooves and ridges, and the shape was more regular, but the depth was not obvious.3. The result of energy distribution spectrumThe concentration of Zr elements in each group at the interface between ceramic and porcelain decline was particularly pronounced.which in the experimental group 2 and the experimental group 3 of the veneering porcelain side of Zr content increased; in the experimental group 1 of the veneering porcelain side detection to trace Zr, and Zr element was not detected in the control group of the veneering porcelain side.In each group, the concentration of Si element at the interface between ceramic and porcelain was decreased rapidly, and the Si element could be detected on the surface of zirconia substrate.In each group, the concentration of Al was decreased at the interface between ceramic and porcelain.Conclusions:1.Compared with the control group, the treatment of single sand blasting or nano zirconia coating can improve the bonding strength of zirconia based ceramic and veneering porcelain.2.Compared with the control group and individually sand blasting or nano zirconia coating group, the combination of sand blasting and nano zirconia coating can significantly improve the bonding strength of zirconia based ceramic and veneering porcelain.3.The diffusion of zirconium elements in the interface between the two layers can be combined with the treatment of nano zirconia coating or sand blasting.which suggests that there may be a combination of chemical.