1. Department of Clinical Dentistry UiT The Arctic University of Norway Tromsø Norway
2. Division of Fixed Prosthodontics and Biomaterials University Clinics for Dental Medicine University of Geneva Geneva Switzerland
3. Department of Reconstructive Dentistry Faculty of Odontology University of Iceland Reykjavik Iceland
4. Clinic of Reconstructive Dentistry Center of Dental Medicine University of Zurich Zurich Switzerland
5. Academic Center for Dentistry Amsterdam (ACTA) Amsterdam the Netherlands
6. Department of Prosthodontics and Biomaterials University Hospital RWTH Aachen Aachen Germany
7. Department of Prosthodontics Center for Dentistry and Oral Medicine Goethe‐University Frankfurt am Main Frankfurt Germany
8. Periodontology and prosthodontics Ospedale Odontoiatrico George Eastman Rome Italy
9. Oral Surgery and Implant Prosthetic Unit, "Sapienza" University of Rome Rome Italy
10. Department of Oral and Maxillofacial Surgery University Medical Center Groningen Groningen the Netherlands
11. Department of Periodontology and Oral Medicine University of Belgrade Belgrade Serbia
12. Department of Prosthodontics, Medical Faculty and University Hospital Düsseldorf Düsseldorf Germany
13. Reconstructive Dentistry University of Ghent Ghent Belgium
14. MOND dental offices Antwerp Belgium
15. Institute of Social and Preventive Medicine (ISPM) University of Bern Bern Switzerland