1. Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, Regensburg, Germany
2. Department of Periodontology, University of Bern, Bern, Switzerland
3. School of Dental Sciences, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
4. Department of Oral Diagnostics, Digital Health and Health Services Research, Charité-Universitätsmedizin Berlin, Berlin, Germany