Effect of differing resin luting systems on fracture resistance of teeth restored with dentin-bonded crowns

Objective: This study investigated the effect of differing bonding and luting system combinations on the fracture resistance of teeth restored with dentin-bonded all-ceramic crowns. Method and materials: Standardized preparations were carried out on five groups, each of 10 sound, unrestored, maxillary premolar teeth. Ceramic crowns were constructed, their internal surfaces were etched with hydrofluoric acid, and the crowns were placed with the following dentin bonding and resin-based luting system combinations: group A, Mirage ABC and Mirage FLC, group B, Metabond luting material; group C, All-Bond 2 and Duo-link; group D, Scotchbond MP Plus and 3M Indirect Porcelain Bonding Kit; and group E, All-Bond 2 and 3M Indirect Porcelain Bonding Kit. The restored teeth were loaded in compression at 1.0 mm/min. Results: Mean fracture loads of 0.77 kN, 0.81 kN, 0.71 kN, 1.24 kN, and 1.03 kN were recorded for groups A, B, C, D, and E, respectively. Statistical analysis indicated that the mean fracture resistance of the restored teeth of groups D and E was significantly greater (P .05) than that of the other three groups. Conclusion: The fracture resistance of dentin-bonded crowns used in this laboratory study was dependent on the bonding and luting systems used.