Active Application on Dentin Bond Durability of Universal Adhesives

Objectives: The aim of this study was to determine the effect of active application in different etching modes on the dentin bond durability of universal adhesives under thermal cycling (TC).
Methods: Three commercially available universal adhesives were used: All-Bond Universal (AB), Adhese Universal (AU), and Scotchbond Universal (SU). Bovine dentin specimens were divided into twelve groups according to the type of adhesive, and subjected to the following bonding procedures: 1) etch and rinse (ER) mode with active application; 2) ER mode with inactive application; 3) self-etch (SE) mode with active application; and 4) SE mode with inactive application. Bonded assembly specimens were stored in distilled water at 37°C for 24 h, and then subjected to 10,000, 30,000, or 50,000 TC between 5 and 55 °C before shear bond strength (SBS) testing.
Results: In the baseline groups, all the tested adhesives with active application had higher SBS values than those with inactive application regardless of the etching mode. In TC groups, significantly lower SBS values were observed at 50,000 TC with inactive application compared to those with active application irrespective of the etching mode. RepresentativeSBS values in SE mode are shown in the table below.
Conclusions: The active application may be helpful for enhancing the dentin bond durability of universal adhesives in both etching modes.