Effect of postponed polishing on marginal adaptation of resin used with dentin-bonding agent

Publisher Website
Google Scholar
Abstract
Dentin cavities, prepared in extracted human teeth, were treated with two different dentin-bonding agents and filled with a light-activated microfilled resin. The maximum width of the contraction gap (MG) and the extent of the gap (GP) were then measured, using a light microscope, approximately 0.1 mm below the original free surface of the filling. The contraction gap was measured 30 s, 10 min or 60 min, and remeasured 65 min, after stop of irradiation. A positive correlation was found between the two variables, MG and GP. The product of MG and GP was chosen as basis for the statistical analyses. This "marginal index" was significantly reduced when polishing of the marginal area was postponed for 10 min with one of the dentinbonding agents and for 60 min with the other. Even though the improvement in marginal adaptation was statistically significant, this improvement was considered clinically irrelevant. It is concluded that polishing of the marginal area should not be done before the hygroscopic expansion of the resin restoration has closed the contraction gap.