1. Division of Gerodontology; School of Dental Medicine; University of Bern; Bern Switzerland
2. Department of Prosthodontics; Preclinical Education and Dental Material Science; University of Bonn; Bonn Germany
3. Division of Fixed Prosthodontics and Biomaterials; Dental University Clinic; University of Geneva; Geneva Switzerland
4. Professor emeritus; School of Dental Medicine; University of Bern; Bern Switzerland
5. Division of Gerodontology and Removable Prosthodontics; University of Geneva; Geneva Switzerland