Microtensile bond strengths of an etch&rinse and self-etch adhesive to enamel and dentin as a function of surface treatment.

In light of the current trend towards "minimal invasive" dentistry, diverse cavity preparation techniques have been introduced as an alternative or addition to common bur instrumentation. This study investigated whether diamond sonoabrasion (SonicSys Micro, Kavo), air abrasion (Prep Start, Danville) and Er:YAG laser irradiation (Fidelis) produce surfaces at enamel/dentin that are equally receptive to bonding as traditional mid-grit diamond-bur (Komet) and 600-grit SiC-paper prepared surfaces, of which the latter two served as controls. An etch&rinse adhesive (OptiBond FL, Kerr) applied with and without prior acid-etching and a self-etch adhesive (Clearfil SE, Kuraray) were employed to bond the restorative composite (Z100, 3M ESPE) to the diversely prepared enamel and dentin surfaces. The microtensile bond strength (microTBS) was determined after 24 hours of storage in water at 37 degrees C. The results indicated that the manner of preparation of enamel and dentin prior to bonding procedures significantly influenced the bonding effectiveness of both the etch&rinse and the self-etch adhesive. Using an etch&rinse adhesive, separate acid-etching of air-abraded and Er:YAG-irradiated enamel and dentin surfaces remains mandatory. Bonding to diamond-sonoabraded and air-abraded enamel and dentin was, in general, not different from bonding to conventional diamond-bur prepared surfaces, whereas, bonding to Er:YAG-irradiated enamel and dentin surfaces in general resulted in a significantly lower bonding effectiveness compared to bonding to diamond-bur prepared surfaces.