IADR Abstract Archives
Adhesion evaluation and scanning electron microscope observation of a deproteinized dentine
Objectives: To evaluate the dentine sealing of composite resin fillings after deproteinization with sodium hypochlorite by quantifying adhesion forces and studying of the adhesive infiltration topography.
Methods: Forty teeth were used for the study. After removal of the occlusal portion, the dentinal surfaces obtained were divided into 2 groups. Composite resin cylinders, FiltekTM Z350 (3M ESPE), were bonded to the dentinal surfaces using a silicone mold. The adhesive used for bonding is the Single Bond Universal (3M ESPE) according to the technique etch and rinse in two steps for the first group and in one-step self etching for the group 2. Each group has been subdivided into 2 subgroups (with or without sodium hypochlorite treatment at 5.25% for 90s). Adhesion was evaluated by the shear strength (SBS) at the resin-dentin interfaces. The dental tissues were then decalcified and deproteinized. A scanning electron microscope observation was performed.
Results: Deproteinization with sodium hypochlorite significantly potentiated dentin adhesion (p> 0.05). Scanning electron microscope showed significantly greater adhesive infiltration after treating the dentinal surfaces with sodium hypochlorite.
Conclusions: Deproteinization potentiates adhesion by significantly increasing surface energy and thus improves the wettability of adhesives. It exposes the mineral fraction of the dentin to the etching acid by removing the organic part of the smear layer and allows the increase of stable phosphate bonds over time.
Methods: Forty teeth were used for the study. After removal of the occlusal portion, the dentinal surfaces obtained were divided into 2 groups. Composite resin cylinders, FiltekTM Z350 (3M ESPE), were bonded to the dentinal surfaces using a silicone mold. The adhesive used for bonding is the Single Bond Universal (3M ESPE) according to the technique etch and rinse in two steps for the first group and in one-step self etching for the group 2. Each group has been subdivided into 2 subgroups (with or without sodium hypochlorite treatment at 5.25% for 90s). Adhesion was evaluated by the shear strength (SBS) at the resin-dentin interfaces. The dental tissues were then decalcified and deproteinized. A scanning electron microscope observation was performed.
Results: Deproteinization with sodium hypochlorite significantly potentiated dentin adhesion (p> 0.05). Scanning electron microscope showed significantly greater adhesive infiltration after treating the dentinal surfaces with sodium hypochlorite.
Conclusions: Deproteinization potentiates adhesion by significantly increasing surface energy and thus improves the wettability of adhesives. It exposes the mineral fraction of the dentin to the etching acid by removing the organic part of the smear layer and allows the increase of stable phosphate bonds over time.