Dentin bond strength of fluoride-releasing materials.

PURPOSE

To evaluate the shear bond strength to dentin of fluoride-releasing materials.

MATERIALS AND METHODS

Human, noncarious extracted permanent molars stored in distilled water were used. Flat buccal and lingual dentin surfaces were ground wet on 600-grit silicon carbide paper. The teeth were then distributed at random into three groups of 8 teeth (16 surfaces) each: Group 1: Compoglass; Group 2: Fuji II LC; Group 3: Dyract. Cylindrical samples of the materials were prepared in plastic molds and bonded to the dentin surface according to the manufacturers' instructions. All samples were placed in distilled water for 24 hours, thermocycled for 500 cycles in distilled water at 6 degrees C and 60 degrees C and sheared with an Instron at a crosshead speed of 0.5 mm/minute.

RESULTS

In MPa: Group 1: 16.29 +/- 5.35; Group 2: 15.42 +/- 4.77; Group 3: 15.33 +/- 6.96. ANOVA revealed that there was no statistically significant difference between the groups. Fracture patterns, examined with the SEM, revealed material cohesive failures for all groups.