Effect of self-adhesive resin cement and tribochemical treatment on bond strength to zirconia.

To evaluate the interactive effects of different self-adhesive resin cements and tribochemical treatment on bond strength to zirconia. The following self-adhesive resin cements for bonding two zirconia blocks were evaluated: Maxcem (MA), Smartcem (SM), Rely X Unicem Aplicap (UN), Breeze (BR), Biscem (BI), Set (SE), and Clearfil SA luting (CL). The specimens were grouped according to conditioning as follows: Group 1, polishing with 600 grit polishing paper; Group 2, silica coating with 110 microm Al2O3 particles which modified with silica; and, Group 3, tribochemical treatment--silica coating + silanization. Specimens were stored in distilled water at 37 degrees C for 24 hours before testing shear bond strength. Silica coating and tribochemical treatment significantly increased the bond strength of the MA, UN, BR, BI, SE and CL to zirconia compared to #600 polishing. For both #600 polished and silica coating treatments, MDP-containing self-adhesive resin cement CL had the highest bond strengths to zirconia. Applying silica coating and tribochemical treatment improved the bond strength of self-adhesive resin cement to zirconia, especially for CL.