1. Department of Cell & Developmental Biology, Dental Research Institute and BK21 Program, School of Dentistry, Seoul National University, Seoul, Republic of Korea.
2. Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan.
3. Department of Periodontology, School of Dentistry, Seoul National University, Seoul, Republic of Korea.
4. Department of Oral Pathology, School of Dentistry, Kyungpook National University, Taegu, Republic of Korea.
5. Department of Biologic and Materials Sciences, University of Michigan, Ann Arbor, Michigan.
6. Macromolecular Science and Engineering Center, University of Michigan, Ann Arbor, Michigan.