1. Research and Development Centre for Tissue Engineering; Fourth Military Medical University; Xi'an Shaanxi People's Republic of China
2. Department of Oral and Maxillofacial Surgery, College of Stomatology; Jiamusi University; Jiamusi Hei Longjiang People's Republic of China
3. Department of Orthodontics, School of Stomatology; Fourth Military Medical University; Xi'an Shaanxi People's Republic of China
4. Department of Oral Histology and Pathology, School of Stomatology; Fourth Military Medical University; Xi'an Shaanxi People's Republic of China