1. Division of Molecular and Regenerative Prosthodontics Tohoku University Graduate School of Dentistry Sendai Miyagi 980‐8575 Japan
2. Dental Stem Cell Biology Research Unit Center of Excellence for Regenerative Dentistry and Department of Anatomy Faculty of Dentistry Chulalongkorn University Bangkok 10330 Thailand
3. Institute of Dentistry Suranaree University of Technology Nakhon Ratchasima 30000 Thailand
4. Department of Material Processing Tohoku University Graduate School of Engineering Sendai Miyagi 980‐8579 Japan
5. Center for Advanced Stem Cell and Regenerative Research Tohoku University Graduate School of Dentistry Sendai Miyagi 980‐8575 Japan