1. Department of Oral and Maxillofacial Diseases Helsinki University Hospital and University of Helsinki Helsinki Finland
2. Division of Nephrology Department of Medicine Helsinki University Hospital Helsinki Finland
3. Institute of Genetics Folkhälsan Research Center Helsinki Finland
4. Department of Virology University of Helsinki Helsinki Finland
5. Department of Oral and Maxillofacial Surgery University of Helsinki and Helsinki University Hospital Helsinki Finland
6. Section of Periodontology and Dental Prevention Division of Oral Diseases Department of Dental Medicine Karolinska Institutet Huddinge Sweden