1. Department of Periodontology and Operative Dentistry; Faculty of Dentistry; University of Münster; Münster Germany
2. Academic Department of Clinical Stomatology; Section of Integral Oral Implantology; Cayetano Heredia Peruvian University; Lima Perú
3. Academic Department of Clinical Stomatology; Section of Periodontology and Implants; Cayetano Heredia Peruvian University; Lima Perú
4. Department of Conservative Dentistry; Heidelberg University; Heidelberg Germany
5. Max Planck Institute for Social Law and Social Policy; Munich Center for the Economics of Aging; Munich Germany