[Bonding durability of commercially-available luting systems for ceramic restoration to dental zirconia]

This study investigated the effects of silanation and adhesive monomer, 10-methacryloyloxydecyl dihydrogen phosphate (MDP), on the bond durability of resin cement to zirconia.

Two sizes of zirconia disk were prepared. The bonding surfaces of the disks were air-particle abraded with 50 microm Al2O3, and then bonded with one MDP-containing or three non-MDP-containing cements to fabricate test specimens. For the silanated specimen group, air-particle abraded surfaces were treated with respective silane coupling agents, including two MDP-containing or two non-MDP-containing agents, before the bonding procedure. Five test specimens for each group were subjected to thermo-cycles before shear bond strengths were determined. The data were statistically analyzed.

For test groups without silanation, the specimens bonded with MDP-containing resin cement showed significantly higher bond strength. In contrast, all specimens bonded with non-MDP-containing resin cements failed during the thermo-cycling process. For the silanated groups, the specimens pre-treated with MDP-containing silane coupling agent and bonded with non-MDP-containing resin cement exhibited the highest shear bond strength. The shear bond strength of specimens pre-treated with MDP-containing silane coupling agent and bonded with MDP-containing resin cement was the next highest. In contrast, all specimens pre-treated with non-MDP-containing silane coupling agent bonded with non-MDP-containing resin cements failed during the thermo-cycling process.

Within the limitations of this study, MDP adhesion monomer was effective in improving the bond durability of resin cement to zirconia.