Bonding of dentin adhesives in clinically-simulated occlusal resin composite restorations

The purpose of this study was to measure the bond strength of resin dentin bonding agents under clinically-simulated conditions. Using extracted human teeth subjected to physiologic-pulpal fluid pressure, occlusal cavity preparations were restored with three dentin bonding agent/resin composite combinations. The teeth were sectioned to remove the occlusal enamel and upper part of the restoration. The force required to remove the remainder of the restoration was converted to a dentin bond strength value. The effect of incremental placement of the resin composite also was investigated. Scotchbond 2 showed better bonding than Gluma or Scotchbond Dual Cure, and Gluma showed better bonding than Scotchbond Dual Cure. Although all materials showed better bonding with the use of three increments of resin composite versus one, only in the case of Scotchbond 2 was there a statistically-verified difference.