1. Laboratory of Epithelial Biology, Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI 48109, USA
2. Department of Stomatology, School of Dentistry, University of São Paulo, Sao Paulo 05508-270, Brazil
3. Oral Diagnosis Department, Piracicaba School of Dentistry, State University of Campinas, Piracicaba 13414-903, Brazil
4. Rogel Cancer Center, University of Michigan, Ann Arbor, MI 48109, USA