1. Department of Periodontology and Geriatric Dentistry; University of Oulu; Oulu Finland
2. Medical Research Unit; Seinäjoki Central Hospital and University of Tampere; Tampere Finland
3. Specialist Dental Health Care Unit; Oulu Finland
4. Department of Medical Microbiology and Immunology; Institute of Diagnostics; University of Oulu; Oulu Finland
5. Department of Bacteriology and Immunology; Haartman Institute; Laboratory Division (HUSLAB); Helsinki University Central Hospital; Helsinki Finland
6. Clinical Microbiology Laboratory; Oulu University Hospital; Oulu Finland
7. Nordlab Oulu; Oulu Finland
8. Institute of Dentistry; University of Eastern Finland; Kuopio Finland
9. Department of Oral and Maxillofacial Surgery; Kuopio University Hospital; Kuopio Finland
10. Oral and Maxillofacial Department; Oulu University Hospital; Oulu Finland