1. Institute for Clinical Performance of Biomaterials (ICPB) and ETN Dental Clinic, 106-B101, 27 Heukseokhangang-ro, Dongjak-gu, Seoul 156-070, Republic of Korea
2. University of Ulsan, College of Medicine, Department of Dentistry, Asan Medical Center, 388-1, Pungnap-2 dong, Songpa-gu, Seoul 138-736, Republic of Korea
3. Institute of Process Engineering, Chinese Academy of Sciences, State Key Laboratory of Multiphase Complex Systems, Beijing, China