1. Institute of Dentistry; University of Helsinki; Helsinki Finland
2. Department of Pathology; Haartman Institute; University of Helsinki; Helsinki Finland
3. Department of Surgery; Helsinki University Central Hospital; Helsinki Finland
4. Department of Otorhinolaryngology and Head and Neck Surgery; Helsinki University Central Hospital; Helsinki Finland
5. University of Helsinki; Helsinki Finland
6. Department of Oral and Maxillofacial Diseases; Helsinki University Central Hospital; Helsinki Finland
7. Health Centre; City of Helsinki; Helsinki Finland
8. Department of Diagnostics and Oral Medicine; University of Oulu; Helsinki Finland
9. Department of Oral Pathology; Institute of Dentistry; University of Helsinki; Helsinki Finland