1. Department of Periodontology, College of Dentistry, University of Florida, Gainesville, FL, USA
2. Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, TN, USA
3. Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, USA
4. The Forsyth Institute, Cambridge, MA, USA
5. Harvard School of Dental Medicine, Boston, MA