ACTA ODONTOLOGICA SCANDINAVICA, cilt.64, sa.5, ss.293-299, 2006 (SCI-Expanded)
Objective. To evaluate the effect of orthotropic fiber-reinforced composite ( FRC) at the interface on bonding of lithium-disilicate ceramic to dentin and enamel using different adhesive systems. Material and Methods. Dentin and enamel surfaces were ground occlusally on human molar teeth. Ceramic blocks of IPS Empress 2 ( Ivoclar-Vivadent) were fabricated. Following acid etching and silane treatment of the xceramics, the teeth were divided into two groups ( dentin and enamel). Ceramic blocks were bonded to the tooth substance with or without a layer of FRC and dual-polymerizing composite cement ( Duolink). Total-etching ( etchant ( Etch 37) with adhesive ( One Step Plus)) and self-etching ( self-priming etchant ( Tyrian SPE) with adhesive ( One Step Plus)) systems were used, with five test specimens in each group. The cement was polymerized with a LED curing unit ( Elipar Freelight LED 2) with standard mode of 40 s. The specimens were thermocycled for 6000 cycles and tested with the microtensile tester at a rate of 5 mm/min. Fracture mode analyses were done by light microscope and with SEM. The data were analyzed using three-way analysis of variance ( ANOVA). Results. ANOVA showed that enamel had statistically significant ( p < 0.001) higher bond strength values than dentin. Bond strength values were significantly higher ( p = 0.012) with the total-etching system than with the self-etching system. The existence of FRC also had a minor effect on bond strength values ( p = 0.013). Conclusions. The enamel and total-etching system provided more reliable bonding than dentin and the self-etching system. Use of an FRC layer at the interface did not improve bond strength values, but instead changed fracture pattern behavior.