1. Department of Periodontology and Oral Implantology; Faculty of Medicine and Health Sciences; Dental School; Ghent University; Ghent Belgium
2. Department of Prosthodontics; Faculty of Odontology; Malmö University; Malmö Sweden
3. Department of Periodontology and Oral Implantology; Faculty of Medicine and Pharmacy; Dental Medicine; Vrije Universiteit Brussel (VUB); Brussels Belgium