Bond strength of composite to etched and sandblasted porcelain
Wolf, D.M.; Powers, J.M.; O'Keefe, K.L.
American Journal of Dentistry 6(3): 155-158
1993
ISSN/ISBN: 0894-8275 PMID: 8240779 Document Number: 406785
In vitro tensile bond strengths of composite to porcelain treated by acid etching or sandblasting were measured. A 9.5% HF gel was applied for 30, 60, 150, or 300 seconds at 23 degrees C. Al2O3 particles were applied as wet-10.2, dry-33.5, dry-48.0, or dry-78.0 microns. Average roughness (Ra) was measured by profilometry before and after each treatment. Both longer etching time and sandblasting using Al2O3 with larger particle sizes produced increased surface roughness of porcelain. Etching with 9.5% hydrofluoric acid gel produced higher bond strengths than sandblasting with a series of Al2O3 particles. Etching longer than 60 seconds produced increased cohesive failures in porcelain, whereas most failures observed with sandblasted surfaces were adhesive.