氧化锆基底和饰瓷结合强度的分析

目的分析和比较几种全瓷系统基底和饰瓷的结合强度。方法制作直径为8 mm、厚度为3 mm的Lava、 Cercon、IPS e.max ZirCAD、Procera试件各20个，分别为Lava组、Cercon组、IPS e.max ZirCAD组、Procera组。每组各选10个试件表面烤制厚度为1 mm的相应饰瓷，10个试件表面烤制厚度为2 mm的相应饰瓷。对试件进行剪切强度的测定和断裂模式的观察。结果饰瓷厚度为1 mm时，Lava、Cercon、IPS e.max ZirCAD、Procera组的剪切强度分别为：（13.82±3.71）、（13.24±2.09）、（6.37±4.15）、（5.19±5.31）MPa；饰瓷厚度为2 mm时，各组的剪切强度分别为：（38.77±1.69）、（21.67±3.34）、（12.70±4.24）、（9.94±6.67）MPa。Lava组和Cercon组的剪切强度高于IPS e.max ZirCAD组和Procera组（P<0.05），饰瓷厚度为2 mm的试件的剪切强度高于饰瓷厚度为1 mm的试件（P<0.05）。各组试件破坏模式均以界面破坏为主。结论氧化锆基底和饰瓷的结合强度因基底材料的不同而不同，饰瓷的厚度对结合强度有明显的影响。

In vitro study on shear bond strength of veneering ceramics to zirconia

Objective To investigate the shear bond strength between veneering ceramic and zirconia core in different all-ceramic systems. Methods Twenty disk-shaped specimens with 8 mm in diameter and 3 mm in height for each zirconia system（Lava, Cercon, IPS e.max ZirCAD, Procera） were fabricated respectively and divided into four groups： Lava group, Cercon group, IPS e.max ZirCAD group, Procera group. For each group, 10 specimens were sintered with 1 mm corresponding veneering ceramic, while the other were sintered with 2 mm corresponding veneering ceramic respectively. The shear bond strength and fracture mode of specimens were observed and determined. Results The values of shear bond strength for Lava, Cercon, IPS e.max ZirCAD and Procera were （13.82±3.71）,（13.24±2.09）,（6.37±4.15）, （5.19±5.31）MPa in the group of 1 mm thicked veneering ceramics, respectively, while the values in the group of 2 mm thicked veneering ceramics were （38.77±1.69）, （21.67±3.34）, （12.70±4.24）, （9.94±6.67）MPa. The values of Lava and Cercon groups were significantly higher than that of IPS e.max ZirCAD and Procera groups（P<0.05）. And the values of 2 mm thicked veneering ceramic group were significantly higher than that in 1 mm thicked groups（P<0.05）. Adhesive fracture between core and veneering ceramics were observed in the fracture modes of most specimens. Conclusion The shear bond strength of veneering ceramic to the zirconia framework are different from the zirconia system we chose, and the thickness of veneering ceramic has a great impact on its shear bond strength.