1. Department of Prosthodontics; Preclinical Education and Dental Materials Science; University of Bonn; Bonn Germany
2. Department of Reconstructive Dentistry and Gerodontology; University of Bern; Bern Switzerland
3. Private Practice; Kreuztal Germany
4. Oral and Maxillofacial Radiology; Applied Oral Sciences; Faculty of Dentistry; Prince Philip Dental Hospital; The University of Hong Kong; Hong Kong China
5. Division of Gerodontology and Removable Prosthodontics; University of Geneva; Geneva Switzerland