1. Department of Orthodontics and DentoFacial Orthopedics, University Hospital of Liège, Belgium
2. Dental Biomaterials Research Unit, Faculty of Medicine, University of Liège, Belgium
3. Department of Periodontolgy and Oral Surgery, University Hospital of Liège, Belgium
4. Biostatistics and Medico-economic Information Department, University Hospital of Liège, University of Liège, Belgium