Bond strengths between gingiva-colored layering resin composite and zirconia frameworks coated with feldspathic porcelain.

This study evaluated shear bond strengths of two gingiva-colored layering resin composites to zirconia frameworks coated with feldspathic porcelain. Airborne-particle abraded porcelain-coated zirconia disks were treated with one of the following primers: Clearfil Photo Bond, Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB+Activator), Estenia Opaque Primer, Porcelain Liner M Liquid B (PLB), or no primer. A light-polymerizing (CER) or a photo/heat-polymerizing gingiva-colored indirect resin composite (EST) was bonded to the porcelain-coated zirconia disks in each group (n=11). Shear bond strength was measured. For both CER and EST specimens, bond strengths in CPB+Act group were significantly higher than those in the other groups. In all priming groups, bond strength was significantly higher for EST specimens than for CER specimens. Combined application of a phosphate monomer and silane enhanced initial bond strength of light-polymerized and photo/heat-polymerized gingiva-colored layering resin composites to porcelain-coated zirconia ceramics.