Marginal seal of new-generation dental bonding agents.

This in vitro study evaluated microleakage of three new adhesive systems--All-Bond 2, Gluma 2000, and Scotchbond Multi-Purpose. Enamel was removed from the buccal surfaces of 40 extracted molars, and cavity preparations were made on both the buccal and lingual surfaces of each tooth. Buccal cavities were entirely in dentin, and the lingual cavities had enamel margins. Specimens were randomly assigned to three groups for treatment with All-Bond 2, Gluma 2000, or Scotchbond Multi-Purpose adhesive systems. A fourth group of specimens was untreated to serve as the control. All cavity preparations were restored with a visible light-cured microfilled composite resin. Specimens were thermocycled and subjected to a crystal violet staining technique to detect marginal microleakage. Microleakage was recorded as ordinal data and analyzed with nonparametric statistical tests. Each of the adhesives tested significantly reduced microleakage at the enamel and dentin margins. The extent of leakage at dentin margins was only slightly greater than at enamel margins in each treatment group.