Development of self-etching primer adhesive in all-in-one bonding system.

The self-etching primer adhesives examined in the present study were aqueous mixtures of 5 wt% MDP, 35 wt% HEMA, 3 wt% 2-hydroxyl-3-(3,4-dimethyl-9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride (QTX), 0.5 wt% ethyl-p-(N,N-dimethylamino)benzoate (EDM), and 30 wt% water-soluble dimethacrylate (i.e., 2,2-bis(4-methacryloxy polyethoxypheny)propane (BPE), Glycerol dimethacrylate (GMR), or Glycerol methacrylate acrylate (GAM)). Self-etching primer adhesive was directly applied to polished bovine teeth. Tensile bond strength of composite resin to bovine teeth was measured after one-day immersion in water at 37 degrees C. Differences in water-soluble dimethacrylate monomer did not produce any significant differences in tensile bond strength to dentin or enamel. The use of N-phenyliminodiacetic acid (PIDAA) instead of EDM showed significantly higher bond strength to dentin and enamel. In conclusion, GMR and GAM were useful as water-soluble dimethacrylates while the combination of PIDAA and QTX was effective in improving the bond strength of composite resin to teeth in an all-in-one bonding system.