1. Faculty of Dentistry; National University of Singapore; Singapore Singapore
2. Department of Biological Sciences; National University of Singapore; Singapore Singapore
3. National University of Singapore Graduate School for Integrative Sciences and Engineering; National University of Singapore; Singapore Singapore
4. Epithelial Cell Biology Laboratory; Institute of Molecular and Cell Biology; Singapore Singapore
5. The Affiliated Stomatology Hospital; Zhejiang University; Hangzhou 310003 China
6. Institute of Medical Biology; Agency for Science Technology and Research; Singapore Singapore
7. Harvard Medical School, and Harvard School of Dental Medicine; Boston MA 02115 USA
8. National University of Singapore Tissue Engineering Program (NUSTEP), Life Sciences Institute; National University of Singapore; Singapore Singapore