1. Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, 3010 Bern, Switzerland
2. Division of Gerodontology and Removable Prosthodontics, University Clinics of Dental Medicine, University of Geneva, 1211 Geneva, Switzerland
3. Department of Prosthodontics, University of São Paulo (USP), São Paulo 05508-900, Brazil
4. Department of Prevention and Oral Rehabilitation, Universidade Federal de Goiás, Goiania 74690-900, Brazil