[1] Univ Med Ctr Hamburg Eppendorf, Dept Oral & Maxillofacial Surg, Div Regenerat Orofacial Med, Hamburg, Germany
[2] BG Trauma Hosp Berlin, Dept Craniomaxillofacial Surg, Berlin, Germany
[3] Univ Clin Dusseldorf, Dept Oral & Maxillofacial Surg, Dusseldorf, Germany
[4] Univ Med Ctr Hamburg Eppendorf, Dept Oral & Maxillofacial Surg, Martinistr 52, D-20246 Hamburg, Germany
[5] Cent South Univ, Xiangya Hosp 2, Dept Stomatol, Changsha, Peoples R China