rhBMP-2对兔下颌骨放疗后骨延长的影响

目的兔下颌骨放射后骨延长的新生骨形成受到轻微抑制,本研究旨在初步了解rhBMP-2对其促进成骨疗效。方法 50Gy组(对照组)和rhBMP-2组(实验组)各兔6只,均在术前1个月接受50Gy放射,间歇8天后,以0.4毫米/次、2次/天的速度进行牵引,固定期6周。实验组在截骨线内同期置入2.0mg rhBMP-2。结果标本和X线均显示两组成骨均良好,与周围骨质无明显的界限;HE组织学切片可见两组骨小梁稀疏、细小,并存在成片状致密纤维结缔组织。图像分析软件结果是:50Gy组和BMP组的骨小梁面积比分别为0.445±0.054和0.459±0.036。经方差分析,两组间差异无统计学意义。结论本研究中的rhBMP-2不能促进兔下颌骨放射后骨延长的新生骨形成。

Effect of rhBMP-2 on Bone Lengthening in Irradiated Rabbit Mandible

Objective To study the effect of rhBMP-2 on new bone formation of bone lengthening which was impaired by radiation in irradiated rabbit mandible.Methods A total of 12 rabbits were randomly divided into 2 groups:An rhBMP-2 group(n=6) and a 50Gy group(n=6).Each rabbit received irradiation of 50Gy.One month after irradiation,the operations were completed.The 2.0mg rhBMP-2 was implanted in the rhBMP-2 group at the same time.After a latency of 8 days,distraction was activated at a rate of 0.4mm,twice a day.The mandibles were harvested 6 weeks after consolidation.Results The specimens and radiographs showed good bone formation.However,the HE stain histology found the sparse,thin bone trabecula and the dense fibrous connective tissue.The bone trabecula area ratio of the rhBMP-2 group was 0.459±0.036 and the 50Gy group was 0.445±0.054(P>0.05).Conclusion The rhBMP-2 could not promote new bone formation in this study.