1. Division of Fixed Prosthodontics and Biomaterials, University Clinic of Dental Medicine, University of Geneva, Rue Michel-Servet 1, 1211 Geneva, Switzerland
2. Department of Prosthodontics, College of Dentistry, Yonsei University, Seoul 03722, Republic of Korea
3. Clinic of Conservative and Preventive Dentistry, Division of Periodontology and Peri-Implant Diseases, Center of Dental Medicine, University of Zürich, 8032 Zürich, Switzerland
4. Clinic of General, Special Care and Geriatric Dentistry, Center of Dental Medicine, University of Zürich, 8032 Zürich, Switzerland