Bond strength of adhesive resin cement with different adhesive systems

To assess the immediate bond strength of a dual-cure adhesive resin cement to the hybridized dentin with different bonding systems. Fifty-six healthy human molars were randomly divided into 7 groups (n=8). After 3 longitudinal sections, the central cuts were included in PVC matrix and were submitted to dentin hybridization according to the groups: G1 - etch & rinse system with 3-step (Apder™ Scotchbond™ Multi-Purpose, 3M ESPE), G2 - etch & rinse system with 3-step (Optibond™ FL, Kerr), G3 - etch & rinse system with 3-step (All-Bond 3®, Bisco), G4 - etch & rinse simplified system (Adper™ Single Bond 2, 3M ESPE), G5 - self-etching system with one step (Bond Force, Tokuyama), G6 - universal system in moist dentin (Single Bond Universal, 3M ESPE), G7 - universal system in dry dentin (Single Bond Universal, 3M ESPE). Then all groups received the cementing of a self-adhesive resin cement cylinder (Duo-link, Bisco) made from a polypropylene matrix. In the evaluation of bond strength, the samples were subjected to the microshear test and evaluated according to the fracture pattern by optical microscopy. The Kruskal-Wallis test suggests a statistically significant difference between groups (p=0,039), and Tukey for multiple comparisons, indicating a statistically significant difference between G3 and G4 (p<0.05). It was verified high prevalence of adhesive failures, followed by mixed failure and cohesive in dentin. The technique and the system used to dentin hybridization are able to affect the immediate bond strength of resin cement dual adhesive

Does hybridized dentin affect bond strength of self-adhesive resin cement?

Background: Evaluate the influence of different hybridization bonding techniques of a self-adhesive resin cement. Material and Methods: 30 human health molars were divided into six groups (n=10). The specimens received three longitudinal sections, allowing insertion of central cuts in PVC matrices. Each group received a different dentin pretreatment according to the manufacturerâ s recommendations, except the control group (G1), as follows. G2 - a 3-step total-etch adhesive system (Optibondâ ¢ FL, Kerr); G3 - a 3-step total-etch adhesive system (Adperâ ¢ Scotchbondâ ¢ Multi-Purpose, 3M ESPE); G4 - a 2-step total-etch adhesive system (Adperâ ¢ Single Bond 2, 3M ESPE); G5 - a single-step self-etching system (Bond Force, Tokuyama); and G6 - universal bonding system (Single Bond Universal, 3M ESPE). Then, cylinders made of self-adhesive resin cement with polypropylene matrix was cemented in all groups (RelyX U200, 3M ESPE). Bond strength was assessed by submitting the specimens to micro-shear test and was characterized according to the fracture pattern observed through optical microscopy. Results: The results were submitted to the Kruskal-Wallis test, which indicated a statistically significant difference between the groups (p=0.04), and Tukeyâ s multiple comparisons, which indicated a statistically significant difference between G1 and G3 (p<0.05). The microscopic analysis revealed a high prevalence of adhesive failures, followed by mixed fractures, and cohesive failures in the dentin. Conclusions: The use of a previous dentin hybridization protocol is able to increase adhesive bonding resistance of self-adhesive resin cement, especially when used Adperâ ¢ Scotchbondâ ¢ Multi-Purpose system