Abstract
This study determined if prior selective enamel etching affected leakage of enamel/dentin margins in Class V low-shrinkage resin-based composite restorations. Round cavities, centered on the cemento/enamel junction, 2 mm in diameter and 2 mm in depth were prepared on the buccal, palatal
or lingual surfaces of premolar teeth to have a total of 60 cavities. One side of the tooth received selective enamel etching and both sides were restored using one of 3 restorative materials (n = 10): Aelite LS posterior/All-bond SE, Estelite Sigma Quick/Bond Force, or Filtek P90/P90
System Adhesive. The teeth were fatigued for 5000 thermal cycles, and the marginal sealing was challenged with 50% ammoniacal silver nitrate. The interface was analyzed and the leakage score was calculated. Two-way ANOVA revealed that Filtek P90 (25.5±17.4) had lower leakage than Estelite
Sigma Quick (63.1±34.5) and Aelite LS Posterior (64.2±41.8) with self-etching. With selective etching, the three materials showed reduced leakage in enamel. A significant difference (P <0.05) was found between leakage in enamel and dentin for the Aelite LS Posterior
selective etch group and for Estelite Sigma Quick. Selective etching reduced enamel leakage for all materials in one-step self-etch materials. Two-step self-etch adhesives bond better to enamel and dentin than one-step resin-based adhesives.