OBJECTIVE To evaluate the shear bond strength to dentin of packable composites using their respective one-bottle adhesives. 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 four groups of 8 teeth (16 surfaces) each: Group 1: Gluma Comfort Bond/Solitaire II; Group 2: Bond 1/Alert; Group 3: Prime & Bond NT/Surefil; Group 4: OptiBond Solo/Prodigy Condensable. Group 5: Single Bond/Z250 (control) 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 hrs, thermocycled for 500 cycles in distilled water at 6 degrees C and 60 degrees C and sheared with a universal testing machine at a crosshead speed of 0.5 mm/min. RESULTS In MPa: Group 1: 24.39 +/- 3.54; Group 2: 28.96 +/- 4.62; Group 3: 30.77 +/- 4.71; Group 4: 30.82 +/- 3.29; Group 5: 24.93 +/- 5.14. ANOVA revealed that Groups 1 and 2 were statistically significantly different from the other groups; there was no statistically significant difference between Groups 2, 3 and 4.