1. Center for Craniofacial Regeneration, University of Pittsburgh, Pittsburgh, PA, USA
2. School of Medicine, Tsinghua University, Beijing, China
3. Department of Periodontics and Preventive Dentistry, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, USA
4. McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, USA
5. Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA, USA
6. Department of Endodontics, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA, USA
7. Department of Biological Sciences, School of Dentistry of Bauru, University of Sao Paulo, Bauru, Brazil