1. Periodontics; Eastman Institute for Oral Health; University of Rochester; Rochester NY USA
2. School of Dentistry; University of California San Francisco; San Francisco CA USA
3. Department of Periodontology; Institute of Odontology; Sahlgrenska Academy; University of Gothenburg; Gothenburg Sweden
4. Periodontal Research Group; Institute of Clinical Sciences; College of Medical & Dental Sciences; University of Birmingham; Birmingham UK
5. Department of Periodontology; Operative and Preventive Dentistry; University of Bonn; Bonn Germany
6. University of Michigan; School of Dentistry; Ann Arbor MI USA
7. University of Texas Health Science Center; San Antonio TX USA
8. Columbia University; College of Dental Medicine; New York NY USA
9. Facultad de Odontologia; Universidad Complutense Madrid; Madrid Spain
10. Periodontology; Faculty of Dentistry; University of Hong Kong; Hong Kong SAR China