1. Department of Periodontology, Faculty of Odontology University of Malmö Malmö Sweden
2. Division of Oral Surgery University Clinic of Dentistry, Medical University of Vienna Vienna Austria
3. Gastrounit, Medical Division Copenhagen University Hospital—Amager and Hvidovre Hvidovre Denmark
4. Copenhagen Center for Inflammatory Bowel Disease in Children, Adolescents and Adults Copenhagen University Hospital—Amager and Hvidovre Hvidovre Denmark
5. Department of Orthodontics and Dentofacial Orthopedics, School of Dental Medicine University of Bern Bern Switzerland
6. Division of Conservative Dentistry and Periodontology University Clinic of Dentistry, Medical University of Vienna Vienna Austria
7. Division of Oral Diseases, Department of Dental Medicine Karolinska Institute Stockholm Sweden