Comparison of sandblasted, ground and melt-etched zirconia crowns regarding adhesion strength to resin cement.

The aim is to compare the adhesion between zirconia and cements attained with melt-etching with potassium hydrogen difluoride, KHF, with that found when such traditional surface treatments as sandblasting and ceramic stone grinding are employed. Groups of zirconia crowns where treated by sandblasting ( = 6), grinding with carbide bur ( = 6) or melt-etching with KHF ( = 6) of the surface before cementation with a resin cement to an implant substitute made by Selective Laser Melting of a cobalt-chromium alloy. Tensile testing was performed to rupture, while measured increasing load at the zirconia-cement interface.