1. Institute of Hard Tissue Development and Regeneration, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
2. Department of Periodontology and Oral Mucosa, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086, P.R. China
3. Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX 75246, USA
4. Department of General Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086, P.R. China
5. The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China