1. Department of Cariology, Endodontology and Pediatric Dentistry, Research Unit of Oral Health Sciences; University of Oulu; Oulu Finland
2. Nordic Institute of Dental Materials (NIOM); Oslo Norway
3. Department of Air Pollution and Noise; Norwegian Institute of Public Health (NIPH); Oslo Norway
4. Oral Health Centre of Expertise in Eastern Norway (OHCE); Oslo Norway