1. Harvard School of Dental Medicine; Harvard University; Boston MA USA
2. Department of Epidemiology, Biostatistics and Occupational Health; McGill University; Montreal QC Canada
3. Sir John Walsh Research Institute; Faculty of Dentistry; The University of Otago; Dunedin New Zealand
4. Oral Pathology Department; Faculty of Dentistry; Universidad de Chile; Santiago Chile
5. School of Dental Medicine; East Carolina University; Greenville NC USA
6. Department of Health Science; The University of Adelaide; Adelaide SA Australia
7. Faculty of Dentistry; The University of Adelaide; Adelaide SA Australia
8. Social and Behavioral Sciences; Harvard T.H. Chan School of Public Health; Boston MA USA