1. Research Unit of Oral Health Sciences; Department of Pedodontics, Cariology and Endodontology; University of Oulu; Oulu Finland
2. Oulu University of Applied Sciences; Oulu Finland
3. Research Unit of Oral Health Sciences; Department of Community Dentistry; University of Oulu; Oulu Finland
4. Medical Research Center; Oulu University Hospital and University of Oulu; Oulu Finland