1. Periodontics Department, College of Dentistry, University of Iowa, Iowa City, IA, USA
2. Division of Oral and Craniofacial Health Sciences, Adams School of Dentistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
3. Department of Biostatistics, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
4. Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN, USA
5. Department of Epidemiology, Johns Hopkins School of Public Health, Johns Hopkins University, Baltimore, MD, USA
6. Division of Epidemiology, Mailman School of Public Health, Columbia University, NY, NY, USA
7. Department of Periodontics, School of Dentistry, Howard University, Washington, DC, USA
8. Division of Comprehensive Oral Health/Periodontology, Adams School of Dentistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA