1. Department of Pediatric Dentistry and Orthodontics Institute of Dentistry, Faculty of Medicine University of Turku Finland
2. Cleft Palate and Craniofacial Center Department of Plastic Surgery Helsinki University Hospital and Helsinki University Finland
3. Research Unit of Population Health Faculty of Medicine, University of Oulu and Medical Research Center Oulu (MRC Oulu), Oulu University Hospital Finland
4. Department of Community Dentistry Institute of Dentistry, Faculty of Medicine, University of Turku Finland
5. Department of Dentistry and Oral Health La Trobe Rural Health School La Trobe University Australia
6. Institute of Dentistry, University of Eastern Finland, Kuopio, Finland, Department of Oral and Maxillofacial Diseases Kuopio University Hospital, Kuopio, Finland and Public Health Evaluation and Projection Unit, National Institute for Health and Welfare Helsinki Finland
7. Centre for Population Health Research University of Turku Turku University Hospital Finland