双梯度羟基磷灰石涂层复合rhBMP-2研究

Study of the Double Hydroxyapatite Coating Incorporated with rhBMP-2

目的 :检验双梯度生物活性涂层假体材料的生物学特性 ;检测rhBMP 2对HA涂层与骨界面之间生物连接的影响。方法 :将同一规格的 3种不同植入体 (Ti、Hati、rhBmp 2HaTi)植入狗股骨 ,术后 3、6、16周分别处死三组动物 ,通过X线照片、不脱钙带植入体的组织切片、计算机图像分析、顶出试验、扫描电镜等检查手段进行观察。结果 :早期骨 -假体界面骨性结合率比较 :Ti <HaTi <rhBmp 2HaTi;早期界面抗剪切强度比较 :Ti <HaTi <rhBmp 2HaTi;6、16周组rhBmp 2HaTi与HaTi植入体界面分离、破坏发生在新生骨内部和骨 -涂层两部分 ,涂层内部无破坏。各种植入体的组织切片均未发现炎症细胞、巨噬细胞浸润。结论 :该种生物活性双梯度羟基磷灰石涂层具有良好的生物相容性和生物力学性能 ;rhBMP 2能促进界面的早期骨性连接。

Objective: To test the biologic characteristics of the double gradient hadroxyapatite (HA) coating and the effects of rhBMP-2 on the biologic connection in the interfaces between bones and implants.Methods:To implant the three kinds of implants into the femurs of nine dogs.Nine dogs were killed at periods of three,six,sixteen weeks after implantation.All specimens were observed and tested by the following methods:posteroanterior roentgenograph,histologic slice,computer digital image analysis system,push-out test,and scanning electron microscopy.Results:The comparing result of the early osseointegration ratios in the interfaces is Ti<HaTi<rhBmp<2HaTi.The comparing result of the interface shear strengths is Ti<HaTi<rhBmp-2HaTi.The interfaced failures of the implants in 6-week group and 16-week group were found all in new bone or on bone-implant interfaces.No failure was found in the coatings.No infiltration of inflammatory cell and macrocyte was found.Conclusion:The bioactive double gradient HA coating had good biocompatibility and good biodynamical character.rhBMP-2 can promote the early bone connection in the interfaces.