Purpose: The aim of this in vitro study was to investigate the resin bond strength and
durability of adhesive bonding systems to densely sintered, pure aluminum oxide
ceramic. Materials and Methods: Acrylic glass tubes filled with composite resin were
bonded to industrially manufactured alumina ceramic disks with an ultrasonically
machined surface. Groups of 20 samples were bonded in an alignment apparatus using
five different bonding methods. Subgroups of 10 bonded samples were tested for tensile
strength following storage in distilled water at 37°C for either 3 or 150 days. In addition,
the 150-day samples were thermocycled 37,500 times. The statistical analyses were
made by the Kruskal-Wallis test, followed by multiple pairwise comparison of the groups
using the Mann-Whitney test. Results: The mean bond strength of a bis-GMA composite
resin to sandblasted alumina ceramic was relatively high after 3 days, at 20 MPa.
Additional silanization or tribochemical silica coating and silanization did not enhance
the bond strength (18 to 20 MPa) and failed spontaneously over long-term storage.
However, using a composite resin containing a special adhesive phosphate monomer, a
statistically significantly higher and durable bond strength to the sandblasted alumina
ceramic surface was achieved after 3 days (50 MPa) and after 150 days of storage (46
MPa). Conclusion: A durable bond strength to pure alumina ceramic was achieved only
by using a composite resin containing an adhesive phosphate monomer after sandblasting
the ceramic surface. Int J Prosthodont 2002;15:333-338.