| Institution: | 1. Institute of Dentistry, University of Helsinki, Helsinki, Finland;2. Department of Oral and Maxillofacial Surgery, Helsinki University Central Hospital, Helsinki, Finland;3. Department of Infectious Disease Surveillance and Control, National Institute for Health and Welfare (THL), Helsinki, Finland;4. Institute of Dentistry, University of Turku, Turku, Finland;5. Unit of Living Conditions, Health and Wellbeing, Department of Environmental Health in Environmental Epidemiology Unit, National Institute for Health and Welfare (THL), Kuopio, Finland |
