1. Division of Endodontics; Department of Oral Biological and Medical Sciences; Faculty of Dentistry; The University of British Columbia; Vancouver BC Canada
2. Department of Materials Engineering; The University of British Columbia; Vancouver BC Canada
3. Center for Biomedical Materials and Engineering; College of Material Science and Chemical Engineering; Harbin Engineering University; Harbin China
4. Department of Stomatology; Tongji Hospital; Tongji Medical College; Huazhong University of Science and Technology; Wuhan China