1. Clinic of General, Special Care, and Geriatric Dentistry Center of Dental Medicine University of Zurich Zurich Switzerland
2. Division of Gerodontology and Removable Prosthodontics University Clinics of Dental Medicine University of Geneva Geneva Switzerland
3. Department of Oral Rehabilitation School of Dentistry Federal University of Goias Goiania Brazil
4. Department of Reconstructive Dentistry and Gerodontology School of Dental Medicine University of Bern Bern Switzerland