Method: Thirty six human third molars were divided in 12 groups (n=6), according to the adhesive used [One-Step (OS), Excite (EX) e Single Bond 2 (SB)], technique (WT, ET) and temperature of volatilization (±23ºC; ±40º C). The occlusal surfaces were flatted, the dentin etched with 35% phosphoric acid (15 s) and rinsed with water. For the groups using the ethanol wet-bonding, the surface was dehydrated with ethanol solutions in an increased sequence of concentration. The adhesives were applied in accordance with the respective group and the tooth restored with a nanofilled resin using an incremental technique. Specimens were stored for 24h, sectioned into beams and stressed to failure at a crosshead speed of 0.5 mm/minute.
Result: Data was statistically analyzed with three-way Analysis of Variance and a Tukey's Test (α=0.05). The temperature of 40º C promoted higher values of bond strength than 23º C, regardless the adhesive and technique used. The adhesive techniques presented similar bond strength. EX obtained higher values than SB and OS, using the ethanol wet-bonding technique, and similar behavior was observed between the adhesives using the water wet-bonding technique.
Conclusion:
Based on these results, it can be concluded that the temperature of 40º C promoted an increase of the bond strength to the adhesives tested, and that EX has better bond strength than SB and OS using the ethanol wet-bonding technique.