1. Faculty of Medicine and Health Sciences; Dental School; Department of Periodontology and Oral Implantology; Ghent University; Ghent Belgium
2. Oral Health Research Group (ORHE); Faculty of Medicine and Pharmacy; Vrije Universiteit Brussel (VUB); Brussels Belgium
3. Faculty of Medicine and Health Sciences; Department of Biomedical statistics; Ghent University; Ghent Belgium