Bonding Effectiveness of a New Universal Adhesive to Caries-Affected Dentin of Primary Molars: An In Vitro Study

Purpose: To evaluate the bonding effectiveness of a new universal adhesive system compared to its predecessor on carious primary dentin using the etch-and-rinse and self-etch techniques. Methods: Twenty human primary molars were subjected to artificial induction of carious dentin and then randomized into four experimental groups according to universal adhesive (Scotchbond Universal Plus, SBU Plus and Scotchbond Universal-SBU) and bonding techniques (etch-and-rinse and self-etch). The adhesives were applied according to the manufacturer's instructions and the starch tube molds were filled with a flowable composite resin. Bond strength was determined using a testing machine and the data were analyzed using two-way analysis of variance. All specimens tested were assessed for failure pattern classification. Results: No significant differences in bond strength values were observed when comparing universal adhesive systems (P=0.83), etching technique (P=0.34) or the cross-interaction adhesive system versus etching technique (P=0.96). Conclusion: Regardless of the bonding technique, SBU Plus showed similar bond strength compared to its predecessor when applied to carious dentin of primary molars.