1. Department of Stomatology, University of Tartu, Tartu, Estonia;
2. Oral and Maxillofacial Unit, Tampere University Hospital, Tampere, Finland;
3. Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland;
4. Faculty of Health Sciences, Institute of Dentistry, University of Eastern Finland, Kuopio, Finland;
5. Department of Oral Development and Orthodontics, Institute of Dentistry, University of Turku, Turku, Finland