1. Oral, Maxillofacial, and Plastic Facial Surgery, J.-W. Goethe University, Frankfurt, Germany.
2. Private Practice, Frankfurt, Germany.
3. Private Practice, Wiesbaden, Germany.
4. Private Practice, Hanau, Germany.
5. Department of Prosthodontics, School of Dentistry, J.-W. Goethe University, Frankfurt, Germany.
6. Department of Pathology, Saar State University, Homburg Saar, Germany.