1. Gottfried Schmalz, DDS, PhD, University of Bern, Department of Preventive, Restorative and Pediatric Dentistry, Freiburgstrasse 7, CH-3010 Bern, Switzerland; University Hospital Regensburg, Department of Conservative Dentistry and Periodontology, Franz-Josef-Strauß-Allee 11, D-93053, Regensburg, Germany
2. Matthias Widbiller, DDS, University Hospital Regensburg, Department of Conservative Dentistry and Periodontology, Regensburg, Germany
3. Kerstin M Galler, DDS, PhD, University Hospital Regensburg, Department of Conservative Dentistry and Periodontology, Regensburg, Germany