AN IN-VITRO STUDY OF 2 ADHESIVE SYSTEMS - 3RD AND 4TH GENERATIONS

The aim of this in vitro study was to compare the adhesive properties of a manufacturer's third and fourth generation dentin adhesive. Vestibular sections of recently extracted third molars were embedded in chemical-cured acrylic resin and ground with 600-grit silicon carbide sandpaper, Fifteen samples were prepared with the adhesive products and the dentin surfaces were analysed by SEM. Twenty-four samples were divided into two groups and prepared with third and fourth generation systems, respectively. Composite filled tubes were then positioned on the prepared dentin surfaces and photopolymerized. The treated samples were kept in distilled water at 37 degrees C for 24 h. Four samples were used to analyze the resin-dentin surface. A tension test was performed on the remaining twenty samples at a crosshead speed of 0.5 mm/min. The results were analyzed using the Fisher and Student t-tests. The fractured surfaces were examined by SEM. The resistance to tensile forces of specimens prepared with the fourth generation system was significantly higher than that obtained after using the third generation system. Thus, as expected from the in vitro tests, the fourth generation system provided better adhesion to dentin than the third generation material.