1. Department for Dentistry, Faculty of Medical Sciences, University of Kragujevac, 34000 Kragujevac, Serbia
2. Faculty of Stomatology, Pancevo, University Business Academy in Novi Sad, 26000 Novi Sad, Serbia
3. Department of Pediatric and Preventive Dentistry with Orthodontics, Faculty of Medicine, University of East Sarajevo, 73300 Foča, Bosnia and Herzegovina
4. School of Dental Medicine, University of Belgrade, 11000 Belgrade, Serbia