[1] Harbin Med Univ, Affiliated Hosp 4, Dept Stomatol, Harbin 150001, Peoples R China
[2] Fourth Mil Med Univ, Sch Stomatol, Dept Operat Dent & Endodont, Shaanxi Key Lab Oral Dis, Xian, Peoples R China
[3] Tian Qing Stem Cell Co Ltd, Natl & Local Joint Stem Cell Res & Engn Ctr Aging, Harbin 150028, Peoples R China
[4] Fourth Mil Med Univ, State Key Lab Mil Stomatol, Xian, Peoples R China
[5] Fourth Mil Med Univ, Natl Clin Res Ctr Oral Dis, Xian, Peoples R China