- Senior resident department of oral and cranio-maxillofacial surgery, Hannover, Germany, 1990-1995. Associate professor Germany, 1994-1995. Head of department oral and cranio-maxillofacial surgery Erlangen-Nuremberg University, Germany, since 1995.
Member German Society of Oral, Dental and Maxillofacial Medicine, German Society of Oral and Cranio-Maxillofacial Surgery, German Society for Skull Base Surgery, Interdisciplinary Group for Cleft Lip and Cleft Palate, German Society of Oral and Dental Implantology, International Association of Oral and Maxillofacial Surgeons, European Association for Osseointegration, American Cleft Palate-Craniofacial Association, Academy of Osseointegration, British Association of Oral and Maxillofacial Surgeons, American Society of Maxillofacial Surgeons, Hellenic Association of Osseointegrated Dental and Maxillofacial Implants-Biomaterials (honorary).
1990 - 1995
1994 - 1995