[1] Xi An Jiao Tong Univ, Coll Stomatol, Key Lab Shaanxi Prov Craniofacial Precis Med Res, Xian, Peoples R China
[2] Xi An Jiao Tong Univ, Coll Stomatol, Dept Periodontol, Xian, Peoples R China
[3] Tongde Hosp Zhejiang Prov, Dept Stomatol, Hangzhou, Peoples R China
[4] China Med Univ, Sch & Hosp Stomatol, Liaoning Prov Key Lab Oral Dis, Dept Periodont, Nanjing North St 117, Shenyang 110002, Liaoning, Peoples R China