Effects of different dentin surface moisture on microtensile bond strength of dentin adhesive systems

Objective To evaluate in vitro the effects of three different dentin surface conditions on microtensile bond strength of two one-bottle dentin adhesive systems. Methods Two one-bottle dentin adhesive systems, Single Bond(SB) and Prime Bond NT (PB),were used to three different dentin surface conditions(dry, wet and overwet).Then resin composit Z-100 was bonded to dentin. The teeth were sectioned and trimmed into hourglass shape. The bonded surface areas of each specimen were about 0.8 mm~2. Microtensile bond strengths were measured. Results For both SB and PB, the wet groups revealed significantly higher bond strength than the dry groups and overwet groups(P0.05). The bond strength of dry groups and overwet groups were not significant different. Under three different dentin surface conditions, the bond strength of SB were all greater than PB. Conclusion When the dentin was applied total-etch one-bottle systems, the dentin surface should be kept appropriately moist.