ISSN:
1708-8240
Quelle:
Blackwell Publishing Journal Backfiles 1879-2005
Thema:
Medizin
Notizen:
Objective: The purpose of this study was to determine the effect of thermal cycling on the enamel bond strengths of two-step adhesive systems, either self-etching primers or “one-bottle” total-etch systems, to bovine enamel. Materials and Methods: Three self-etching primer systems–Imperva Fluoro Bond® (Shofu Inc., Kyoto, Japan), Clearfil® Liner Bond II (Kuraray Co. Ltd., Osaka, Japan), and Mac Bond® II (Tokuyama Corp., Tokyo, Japan)–and four total-etch adhesive systems–One-Step® (Bisco Inc., Schaumburg, IL, USA), Opti-Bond Solo® (Kerr Corporation, Orange, CA, USA), Prime & Bond® 2.0 (Dentsply DeTrey, Konstanz, Germany), and Single BondTM (3M ESPE, St. Paul, MN, USA)–were used. Labial enamel surfaces of bovine incisors were exposed by grinding with 240-grit and 600-grit wet silicon carbide paper. Enamel was treated according to the manufacturers' instructions. Following the application of adhesive resin, resin composites were condensed into a mold (diameter = 4 mm, depth = 2 mm) and were light-cured. Bonded specimens were stored in 37°C water for 24 hours. They were divided into a control group (no thermal cycling) and three experimental groups with thermal cycles of 3,000, 10,000, and 30,000 cycles, respectively, between 5°C and 60°C. The shear test was performed at a crosshead speed of 1.0 mm/min. The ultrastructure of resin-enamel interfaces was observed by SEM at times 3,500 magnification. Results: Self-etching primer systems had significant decreases in enamel bond strengths with thermal cycling. In contrast, total-etch systems had no significant differences, except for One-Step. Mixed failures were predominant in these systems, but adhesive failures tended to increase with a greater number of thermal cycles. SEM observations revealed small cracks at the resin-enamel interface for self-etching primer systems when subjected to 30,000 thermal cycles. Conclusions: Enamel shear bond strengths after thermal cycling of self-etching primer systems appeared to be less stable than were those of total-etch adhesive systems.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1111/j.1708-8240.2004.tb00459.x
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