1. Private Practice, Athens, Greece
2. Department of Orthodontics, School of Dentistry, National and Kapodistrian University of Athens, Athens, Greece
3. Department of Orthodontics, Faculty of Dentistry, School of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
4. Department of Hygiene, Epidemiology and Medical Statistics, School of Medicine, National and Kapodistrian University of Athens, Athens, Greece
5. Department of Orthodontics, School of Dental Medicine Case Western Reserve University, Cleveland, OH, USA