The influence of different stress modalities on tensile bond strength

The aim of the present investigation was to evaluate the influence of four different stress simulations on tensile bond strength of a single-component dentin adhesive (Excite). Therefore sixty caries-free third molars, stored in saline for a maximum of seven days after extraction, were used. All teeth were prepared in a special manner allowing the simulation of the dentin perfusion. Dentin specimen with a thickness of 3.5 mm were obtained under standardized conditions. The specimen were randomly assigned to four experimental groups of 15 each. Tensile bond strength after four different stress modalities (group A: max. load without cycles; group B: max. load after increasing cycles; group C: max. load after 100 constant cycles; group D: max. load after 200 constant cycles) was evaluated using an universal testing machine 15 minutes after application and light curing of the composite material (Tetric Ceram, colour A2). Following tensile bond strength were evaluated in MPa:Group A: 5.25 (± 0.87), Group B: 4.01 (± 1.10), Group C 5.80 (± 2.11), Group D: 8.23 (± 1.24). Statistical analysis showed a significant influence of the different stress modifications on tensile bond strength (p Parole chiave: dentin, dentin bonding, tensile bond strength, dentin bonding agent