Cochran D L, Nummikoski P V, Jones A A, Makins S R, Turek T J, Buser D
Department of Periodontics, University of Texas Health Science Center at San Antonio 78284-7894, USA.
Int J Oral Maxillofac Implants. 1997 Nov-Dec;12(6):739-48.
Ideal endosseous implant placement involves a congruent bony housing in close apposition to the implant surface. Clinical situations are encountered, however, in which the entire implant surface cannot be in close apposition to bone. In these instances, bone grafting materials are generally used to regenerate bone around the implant. In this study, a biologically active bone differentiation factor, recombinant human bone morphogenetic protein-2 (rhBMP-2), was used with two different carriers to regenerate bone around implants in standardized critical-sized defects in the canine mandible. Half of the sites had a nonresorbable membrane placed over the defect. Longitudinal standardized radiographs were obtained to assess the amount of bone regeneration on the mesial and distal of the implants after 4 and 12 weeks of healing. Ninety-six implants were placed in 12 fox-hounds. Bone fill was determined by linear measurement of bone on the radiographs, and changes in bone density were evaluated by computer-assisted densitometric image analysis of discrete areas adjacent to the implant. After 4 weeks of healing, nonmembrane sites had significantly greater bone height than membrane-protected sites. Following 12 weeks of healing, sites treated with rhBMP-2 had significantly greater bone formation than untreated sites. Sites treated with rhBMP-2 and a membrane had the greatest bone fill, followed by sites treated with rhBMP-2 but no membrane. Sites without rhBMP-2, whether with or without a membrane, had less bone fill than sites with rhBMP-2. At 12 weeks, sites with a membrane resulted in significantly more gain in bone density than sites without a membrane. Furthermore, sites treated with a collagen carrier resulted in greater gains in bone density than sites treated with a polylactide/glycolide carrier. The results from this study demonstrate by radiographic evidence that new bone formation in critical-sized defects around implants is dependent on time after defect treatment, the type of carrier used, the use of a barrier membrane, and the presence of rhBMP-2. In addition, these findings suggest that rhBMP-2, a bone differentiation factor, can significantly stimulate bone formation around endosseous dental implants.
理想的骨内种植体植入需要与种植体表面紧密贴合的一致骨腔。然而，在临床情况中，会遇到整个种植体表面无法与骨紧密贴合的情况。在这些情况下，通常使用骨移植材料在种植体周围再生骨。在本研究中，一种生物活性骨分化因子，重组人骨形态发生蛋白-2（rhBMP-2），与两种不同的载体一起用于在犬下颌骨标准化临界尺寸缺损的种植体周围再生骨。一半的部位在缺损上方放置了不可吸收膜。在愈合4周和12周后，获取纵向标准化X线片以评估种植体近中和远中侧的骨再生量。将96枚种植体植入12只猎狐犬体内。通过对X线片上的骨进行线性测量来确定骨填充情况，并通过对种植体相邻离散区域进行计算机辅助密度图像分析来评估骨密度变化。愈合4周后，无膜部位的骨高度明显高于膜保护部位。愈合12周后，用rhBMP-2治疗的部位比未治疗部位有明显更多的骨形成。用rhBMP-2和膜治疗的部位骨填充最多，其次是用rhBMP-2但无膜治疗的部位。没有rhBMP-2的部位，无论有无膜，其骨填充都比有rhBMP-2的部位少。在12周时，有膜部位的骨密度增加明显多于无膜部位。此外，用胶原载体治疗的部位比用聚丙交酯/乙交酯载体治疗的部位骨密度增加更多。本研究结果通过影像学证据表明，种植体周围临界尺寸缺损中的新骨形成取决于缺损治疗后的时间、所用载体的类型、屏障膜的使用以及rhBMP-2的存在。此外，这些发现表明，骨分化因子rhBMP-2可显著刺激牙骨内种植体周围的骨形成。
