1 Department of Dental Medicine, Division of Periodontology, Karolinska Institutet, Huddinge, Sweden. Electronic address: Dalia.Khalil@ki.se.
2 Department of Dental Medicine, Division of Periodontology, Karolinska Institutet, Huddinge, Sweden.
3 Swedish Public Dental Service, Uppsala, Sweden.
4 Swedish Public Dental Service, Örebro, Sweden.
5 Swedish Public Dental Service, akademiska sjukhuset, Uppsala, Sweden.
6 Department of Dental Medicine, Division of Orofacial Diagnostics and Surgery, Karolinska Institutet, Huddinge, Sweden; Department of Oral and Maxillofacial Surgery, Karolinska University Hospital, Stockholm, Sweden.