The effects of coatings with three different SiO_2 thickness on shear bonding strength of zirconia ceramics to the opaque dentin porcelain

Objective To evaluate the effects of coatings of three different SiO2 thickness on shear bonding strength of zirconia ceramics to the opaque dentin porcelain.Methods Blocks of sintered zirconia ceramics were randomly divided into 3 groups with 16 slices in each,treated with SiO2 of 3 different thickness coating respectively,(① 100 nm coating ② 200 nm coating ③ 300 nm coating),and then bonded to opaque dentin porcelain.The shear bonding strength of each group was tested,and the data were then analyzed by SPSS 13.0.Results The group of 200 nm gained the highest shear bonding strength,which was significantly different from the group of 100 nm and 300 nm(P0.05).Conclusion A thickness of 200 nm coating is the best option to the zirconia ceramics,which can enhance the shear bonding strength between the zirconia ceramics and opaque dentin porcelain.