1. Department of Oral and Maxillofacial Surgery, Ludwig Maximilians Universität, München, Germany
2. Clinic for Oral and Craniomaxillofacial Surgery, University Hospital Basel, Basel, Switzerland
3. Department of Oral and Maxillofacial Surgery, University Hospital Marburg, Marburg, Germany
4. Department of Otolarynology-Head and Neck Surgery, SUNY Upstate Medical University, New York
5. AO Clinical Investigation and Documentation, AO Foundation, Dübendorf, Switzerland
6. Department of Research and Development, Schulthess Clinic, Zürich, Switzerland