1. Department of Plastic, Hand- and Reconstructive Surgery, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, D-93053 Regensburg, Germany
2. Clinic and Polyclinic for Oral and Maxillofacial Surgery, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, D-93053 Regensburg, Germany
3. Department of Plastic, Hand- and Reconstructive Surgery, Ernst von Bergmann Klinikum Potsdam, Charlottenstraße 72, D-14467 Potsdam, Germany