Affiliation: | 1. Department of Periodontology and Geriatric Dentistry, University of Oulu, , Oulu, Finland;2. Medical Informatics and Statistics Research Group, Oulu University, , Oulu, Finland;3. Department of Medical Microbiology and Immunology, Institute of Diagnostics, University of Oulu, , Oulu, Finland;4. Clinical Microbiology Laboratory, Oulu University Hospital, , Oulu, Finland;5. Health Centre of Oulu, , Oulu, Finland;6. Department of Primary Health Care, Vaasa Central Hospital, , Vaasa, Finland;7. Specialist Dental Health Care Unit, , Oulu, Finland;8. Medical Research Unit, Sein?joki Central Hospital and University of Tampere, , Tampere, Finland;9. Laboratory, Oulu University Hospital, , Oulu, Finland;10. Department of Clinical Chemistry, Institute of Diagnostics, University of Oulu, , Oulu, Finland;11. Department of Bacteriology and Immunology, Laboratory Division (HUSLAB), Haartman Institute, Helsinki University Central Hospital, University of Helsinki, , Helsinki, Finland;12. Oral and Maxillofacial Department, Oulu University Hospital, , Oulu, Finland |