[1] Univ Turku, Inst Dent, Dept Periodontol, Turku, Finland
[2] Hebrew Univ Jerusalem Hadassah Hosp & Med Sch, Fac Med Dent, Dept Periodontol, Jerusalem, Israel
[3] Dublin Dent Univ Hosp, Trinity Coll, Div Restorat Dent & Periodontol, Dublin, Ireland
[4] Univ Complutense, Fac Odontol, ETEP Etiol & Therapy Periodontal Dis Res Grp, Madrid, Spain
[5] Newcastle Univ, Ctr Oral Hlth Res, Newcastle Upon Tyne, Tyne & Wear, England
[6] Newcastle Univ, Inst Cellular Med, Newcastle Upon Tyne, Tyne & Wear, England
[7] Univ Hosp Wuerzburg, Dept Periodontol, Wurzburg, Germany
[8] Univ Ferrara, Sch Dent, Ferrara, Italy
[9] Univ Ferrara, Res Ctr Study Periodontal & Peri Implant Dis, Ferrara, Italy
[10] Istanbul Univ, Dept Periodontol, Istanbul, Turkey