1. Department of Periodontology, Institute of Dentistry, University of Turku, Lemminkäisenkatu 2, 20520 Turku, Finland
2. Department of Periodontology, Faculty of Dentistry, Medipol University, Goztepe Mahallesi, Ataturk Caddesi 40, Beykoz, 34815 Istanbul, Turkey
3. Welfare Division, Oral Health Care, 20540 Turku, Finland