外源性碱性成纤维细胞生长因子促膜引导性骨再生的实验研究

本实验旨在评估碱性成纤维细胞生长因子 (bFGF)对于膜引导性骨再生 (MGBR)的作用。取 4 0只成年新西兰大白兔 ,以聚 DL 乳酸膜建立经典的兔桡骨缺损膜引导性骨再生模型 ,实验侧膜管内加入游离bFGF4 0 μg/10 0 μl,对照侧膜管内加入 10 0 μl的生理盐水。术后 2、4、8、12周分别处死动物 ,行大体观察、X线摄片、组织学观察和图像分析以及骨生物力学检测。术后 2周 ,可见隔膜两端的软组织已覆盖隔膜管 ,使其形成完全密闭的腔室 ,术后 12周PDLLA膜管仍保持完整的外形。组织学显示 :术后 2周 ,bFGF组两骨断端均有较多的新生骨小梁形成 ,术后 12周 ,bFGF组缺损完全愈合 ,开始重塑改建。术后 2周、4周 ,bFGF组膜管内新生骨小梁平均面积、直径均与空白对照组比较明显增加 (P <0 .0 5 ) ,术后 8周和 12周 ,两组膜管内骨小梁平均面积、直径差异无显著性 (P >0 0 5 )。 12周时除了破坏挠度值 ,bFGF组新生骨生物力学指标优于对照组 (P <0 .0 5 )。因此 ,作者认为外源性bFGF能够促进MGBR及其生物力学性能的恢复。

Experimental Studies on Exterior bFGF for Enhancement of Membrane Guided Bone Regeneration

These studies sought to evaluate the promoting effect of the exterior bFGF on membrane guided bone regeneration (MGBR). Animal models of MGBR covered with PDLLA membrane tube in bilateral radii were established in 40 New Zealand white rabbits. The membrane tubes on the left side were filled with bFGF 40 microg/100 microl and those on the contralateral side were filled with 100 microl 0.9% NaCl solution as control. The specimens were collected at 2, 4, 8, 12 weeks postoperatively. General observation, X-ray, histological grading and HE staining,and biomechanical examination were applied to studies on the repair of the models of MGBR in the two groups. Two weeks after operation, a sealed room was formed between the two bone fragments where the soft tissues covered the membrane tube. Twelve weeks after operation, PDLLA membrane became fragile and its tube shape was being maintained. Histologically, in the bFGF group numerous newly formed bone trabeculae were seen at 2 weeks after operation the radial defects had healed and the bone reconstruction and remodling had begun by the 12th week. The histological image analysis showed that the values of mean diameter and the area of new bone trabeculae in the bFGF group were higher than those in the control group (P<0.05) at 2 weeks and 4 weeks; however, there were no significant differences in these aspects between the two groups (P>0.05) at 8 and 12 weeks. The strength of the newly formed bone in the bFGF group was higher than that in the control group at 12 weeks postoperatively (P<0.05). Therefore, the authors concluded that bFGF could promote the new bone formation and biomechanical strength in the MGBR model.