4Chuang S K,Cai T,Douqlass C W,et al.Frailty approach for the analysis of clustered failure time observations in dental research[J].J Dent Res,2005,84(1):54-58.
4Horowitz RA. Extraction environment enhancement: critical evaluation of early socket healing in long-term barrier-protected extraction sockets. Compend Contin Edue Dent, 2005, 26(10) : 703-713.
5Irinakis T, Tabesh M. Preserving the socket dimensions with bone grafting in single sites: an esthetic surgical approach when planning delayed implant placement. J Oral Implantol, 2007,33 (.3) : 156-163.
6Lazzara RJ. Immediate implant placement into extraction sites: surgical and restorative advantages. Int J Periodontics Restorative Dent, 1989,9 (5) : 332-343.
7Zubillaga G, Von Hagen S, Simon BI,et al. Changes in alveolar bone height and width following post-extraction ridge augmentation using a fixed bioresorbable membrane and demineralized freeze- dried bone osteoinductive graft. J Periodontol, 2003,74 (7): 965-975.
8Schropp L, Wenzel A, Kostopoulos L, et al. Bone healing and soft tissue contour changes following single-tooth extraction: a clinical and radiographic 12-month prospective study. Int J Periodontics Restorative Dent, 2003, 23(4) : 313-323.
9Simpson HE. Experimental investigation into the healing of extraction wounds in macacus rhesus monkeys. J Oral Surg Anesth Hosp Dent Serv, 1960, 18 : 391-399.
10Becker W, Clokie C, Sennerby L, et al. Histologic findings after implantation and evaluation of different grafting materials and titanium micro screws into extraction sockets: case reports. J Periodontol, 1998, 69(4) : 414-421.