Effects of cements and eugenol on properties of a visible light-cured composite.

An in vitro study evaluated the effects of barrier materials on mechanical properties of a visible light-cured composite restorative. The composite was cured and aged over a widely used cavity liner (Dycal), various cements (Fleck's, Durelon, Vitrabond, ZOE B & T) and free eugenol and tested at seven and 28 days. The properties of interest were tensile stress (strength) at rupture, compressive strain (deformation at rupture), and stress-strain ratio at rupture. The experiment indicated that underlying barrier materials exerted neither a beneficial nor an adverse effect upon the restorative's ability to withstand compressive strain and tensile stress (P < 0.05).