1. Department of Reconstructive Dentistry & GerodontologySchool of Dental Medicine, University of Bern Bern Switzerland
2. Department of Oral Surgery & Stomatology, School of Dental MedicineUniversity of Bern Bern Switzerland
3. Division of Oral Health & SocietyMcGill University Montreal Canada
4. Division of Fixed Prosthodontics & Biomaterials, School of Dental Medicine, Faculty of MedicineUniversity of Geneva Geneva Switzerland