[Scanning electronmicroscopic studies on the behavior of so-called caustic-adhesive composite resins]

Two new caustic-adhesive composite resins (Concise-Enamel-Bond and Nuva-Seal/Nuva-Fil) were tested in experimentally prepared flat cavities in extracted human teeth under the scanning electron microscope. On the basis of the findings, possible failures with this filling technique resulting from insufficient adhesion of the "sealer" at the enamel are discussed, and practical proposals worked out (utilization of rubber dam, final coating with the sealer to improve surface quality and prevent marginal gaps).