Affiliation: | 1. Division of Fixed Prosthodontics, School of Dental Medicine, University of Bern, , Bern, Switzerland;2. Department of Oral Surgery and Stomatology, School of Dental Medicine, University of Bern, , Bern, Switzerland;3. Department of Periodontology, School of Dental Medicine, University of Bern, , Bern, Switzerland;4. School of Dental Medicine, University of Bern, , Bern, Switzerland |