Affiliation: | 1. City of Helsinki, Department of Social Services and Health Care, Oral Health Care, Helsinki, Finland;2. Department of Oral and Maxillofacial Diseases, Faculty of Medicine, University of Helsinki, Helsinki, Finland;3. Department of Oral and Maxillofacial Diseases, Faculty of Medicine, University of Helsinki, Helsinki, Finland Institute of Dentistry, University of Eastern Finland, Kuopio, Finland Kuopio University Hospital, Oral and Maxillofacial Diseases, Kuopio, Finland;4. Department of General Practice and Primary Health Care, University of Helsinki, Helsinki, Finland Helsinki University Hospital, Unit of Primary Health Care, Helsinki, Finland |