1. Clinic of Fixed and Removable Prosthodontics and Dental Material Science; Center of Dental Medicine; University of Zurich; Zurich Switzerland
2. Department of Prosthetic Dentistry; Faculty of Medicine; Center for Dental Medicine; Medical Center; University of Freiburg; Freiburg Germany
3. Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin (CBF); CC 3 Dental and Craniofacial Sciences; Department of Prosthodontics; Geriatric Dentistry and Craniomandibular Disorders; Berlin Germany
4. Center for Medical Biometry and Medical Informatics; Institute for Medical Biometry and Statistics; University Medical Center Freiburg; Freiburg Germany