Effect of mode of application on the microtensile bond strength of a self-etch and etch-and-rinse adhesive system

This study examined the 24-hour microtensile bond strength (microTBS) of a three-step etch-and-rinse (All Bond 3 [AB3]) and a two-step self-etch system (All Bond Self-Etch [ABSE]) to dentin and ground enamel, varying the application mode.

AB3 was applied according to the following procedures: A-phosphoric acid + adhesive application. The adhesive was then light-cured before resin buildup. B-similar to Procedure A, except that a thin layer of bonding resin was applied over the cured adhesive; C-similar to Procedure B, however, the adhesive was not light-cured before application of the bonding resin. ABSE was applied according to the following procedures: A--the acidic adhesive was applied and light-cured; B--after the acidic adhesive application and light-curing, a thin layer of ABSE Liner was applied and light cured; C--similar to B, however, the acidic adhesive was not light cured before application of the ABSE Liner. Resin composite buildups (Charisma) were bonded to teeth substrates after adhesive application. The bonded specimens were sectioned into beams 0.9 mm2 after storage in water (24 hours/37 degrees C) and subjected to microTBS with a crosshead speed of 0.5 mm/minute. The average values (MPa) obtained in each substrate were subjected to two-way repeated measures ANOVA and the Tukey's test (alpha=0.05).

No significant difference was observed among the experimental groups either in ground enamel or dentin.

The 24-hour microtensile bond strength of All Bond 3 and All Bond Self-Etch was similar, regardless the mode of application of the adhesive systems.