[1] Univ Zurich, Ctr Dent Med, Clin Prevent Dent Periodontol & Cariol, Zurich, Switzerland
[2] Univ Helsinki, Dept Oral & Maxillofacial Dis, Helsinki, Finland
[3] Helsinki Univ Hosp, Helsinki, Finland
[4] Karolinska Inst, Div Periodontol, Dept Dent Med, Stockholm, Sweden
[5] Dentognostics GmbH, Inst Mol Diagnost, Solingen, Germany
[6] Dentognostics GmbH, Inst Mol Diagnost, Jena, Germany