Influence of temporary filling materials on effect of dentin-bonding agents

Dentin cavities, prepared in extracted human teeth, were filled with a dry mixture of zinc oxide-eugenol (ZOE) or a commercial temporary filling cement without eugenol (Cavit). The ZOE was removed 3 h later while the Cavit was removed after 7 days. The cavity wall and the surrounding dentin were then treated with a dentin-bonding agent before application of a restorative resin. The width and the extent of the marginal contraction gap were measured, using a light microscope, approximately 0.1 mm below the original free surface of the filling. It was found that the contraction gap was markedly increased in cavities previously filled with ZOE while the non-eugenol cement had no influence on the effect of the two dentin-bonding agents tested. The short-term test applied in the present study indicates that ZOE should not be used in cavities later to be restored with dentin-bonding agent and resin.