Purpose: The purpose of the current study was to evaluate the effect of acidic primers on the bond strength and durability of an acrylic resin luting agent to zirconia. Materials and Methods: Disk specimens were fabricated from zirconia partially stabilized with yttrium oxide (Katana, Noritake Dental Supply). The disks were treated with one of the following acidic primers: Acryl Bond (Shofu), All Bond II Primer B (Bisco), Alloy Primer (Kuraray), Estenia Opaque Primer (Kuraray), Eye Sight Opaque Primer (Kanebo), M.L. Primer (Shofu), MR. Bond (Tokuyama Dental), or Super-Bond Liquid (Sun Medical). Unprimed specimens served as the control. The disks were bonded with a tri-n-butylborane (TBB)-initiated acrylic resin. Shear bond strengths were determined both before and after 10,000 thermocycles (5°C and 55°C, 1 min dwell time each). Results: The pre-thermocycling bond strength ranged from 0.7 MPa to 30.8 MPa, whereas post-thermocycling bond strength varied from 0.3 MPa to 17.6 MPa. The significantly highest post-thermocycling bond strength was obtained when using the Alloy Primer and Estenia Opaque Primer agents. Conclusion: Within the limitations of the current experiment, it can be concluded that application of either the Alloy Primer or the Estenia Opaque Primer, both of which contain 10-methacryloyloxydecyl dihydrogen phosphate (MDP), is recommended for bonding the Katana zirconia material with TBB-initiated acrylic resin.
Keywords: bonding, phosphate, primer, zirconia