1. Department of Oral, Maxillofacial and Plastic Surgery; University Medical Centre Rostock; Rostock Germany
2. Department of Oral, Maxillofacial and Plastic Surgery; University Medical Centre Mainz; Mainz Germany
3. Dental Private Praxis; Nieuwegein The Netherlands
4. Department of Operative Dentistry; University Medical Centre Mainz; Mainz Germany
5. Dental Surgery Outpatient Clinic; University Medical Centre Mainz; Mainz Germany