Four-year in vivo evaluation of the composite/bonding resin-tooth interface

The objective of this study was to evaluate the color match, marginal discoloration, recurrent caries, anatomic form, and marginal adaptation of 41 paired Class III and Class V preparations restored with a conventional chemically cured resin composite with and without a low-viscosity bonding resin (LVBR). In addition, the wear of the restorations was evaluated from scanning electron micrographs of epoxy replicas of the restorations. The subjects were re-called 48 months after placement of the restorations. The marginal discoloration and wear of the composite restorations placed without a LVBR were significantly greater than in restorations placed with a LVBR. The results of this clinical study suggest that a LVBR should be applied prior to the placement of a conventional chemical-activated resin composite.