1. Institute of Dentistry, University of Eastern Finland, Kuopio, Finland;
2. Public Health Evaluation and Projection Unit, National Institute for Health and Welfare, Helsinki, Finland;
3. Department of Oral and Maxillofacial Diseases, Kuopio University Hospital, Kuopio, Finland;
4. Department of Social Services and Health Care, City of Helsinki, Helsinki, Finland;
5. Insurance Medicine Unit, Benefit Services, The Social Insurance Institution, Helsinki, Finland;
6. Department for Social and Health Services, Ministry of Social Affairs and Health, Helsinki, Finland;
7. Department of Community Dentistry, Institute of Dentistry, University of Turku, Turku, Finland;
8. Medical Research Center, Oulu University Hospital & Oulu University, Oulu, Finland