Website Opinion on Sandblasting Zirconia Substrates

We at Danville have been aware of research by Van Thompson et al that suggests sandblasting the intaglio indirect restorations that are comprised of zirconia with Al2O3 powder can create weakness in these crowns or substructures1. That weakness could in theory contribute to fractures resulting from occlusal loading. Thompson has stated to Danville "Since we see few frame work failures with ziconia, sandblasting with low pressure seems reasonable."

M. Kern et al in Germany have shown in a series of papers that 50 micron Al2O3 sandblasting followed by Panavia bonding is strong and durable2. Furthermore, CoJet (3M/ESPE) sandblasting with modified 38 micron Al2O3 powder at 40 psi is widely reported to be successful with zirconia bonding.

In conversation with Michael Miller, founder of Reality, he stated, "I don’t believe that sandblasting ceramics (if done properly) causes any damage to the surface that would result in failure. The factors that affect this are the type of tip (inside diameter), distance from the ceramic, particle size and how long the treatment is applied." Reality’s research on Bisco's Z Prime seems to support safe use of Al2O3 powder in surface treatment. This study shows use of 50 micron powder at 70 psi will produce the best results when coupled with the Z Prime3.

Donassollo et al in their study, "Resin bond strength to a zirconia reinforced ceramic after different surface treatments4," stated that silica coated substrate (CoJet) with silane coating fared best in micro tensile bond testing.

In light of the research read and the conversations with leading clinicians, Danville recommends sandblasting to enhance adhesion providing the following guidelines are followed:

  1. Al2O3 particles should be 50 micron or less.
  2. Air pressure should not exceed 45 psi.
  3. CoJet or similar substances used as bond enhancers can be used per the manufacturer's recommendations.



Questions should be addressed to Dr. Patrick Roetzer at Danville.

Patrick L. Roetzer, DDS, FICD
VP/Director of Clinical Affairs

Danville Materials, Inc
1 (800) 827-7940 Ext 227
1 (707) 592-7526 Mobile