1. Department of Oral-, Maxillo- and Plastic Facial Surgery, Heinrich-Heine-University Duesseldorf, Duesseldorf, Germany
2. Department of Otolaryngology, University of California Davis School of Medicine, Sacramento, CA, USA
3. Plastic and Reconstructive Surgery at the R. Adams Cowley Shock Trauma Center, University of Maryland Medical Center, Baltimore, MD, USA
4. Department of Oral-, Maxillo- and Plastic Facial Surgery, University of Ulm, Ulm, Germany
5. Department of Oral-, Maxillo- and Plastic Facial Surgery, University of Hannover, Hannover, Germany