摘要
目的研究以聚-DL-乳酸(poly-D,L-lacticacid,PDLLA)为载体复合rhBMP-2接骨板的制备,并观察其生物相容性,为临床应用提供理论依据。方法将rhBMP-2以0.05mg/板与PDLLA真空负压抽吸复合,制备复合rhBMP-2的PDLLA接骨板。新西兰大白兔32只,雌雄不限,体重(3.0±0.5)kg。制备双侧尺骨中段2.5mm骨及骨膜缺损模型。取右侧为实验组(n=32),采用复合rhBMP-2的PDLLA接骨板固定尺骨骨折处;左侧为对照组(n=32),采用普通PDLLA接骨板固定。于术后2、4、8和12周行大体、X线片和组织学观察,比较复合rhBMP-2的PDLLA接骨板与普通PDLLA接骨板的生物相容性。结果复合rhBMP-2的PDLLA接骨板孔隙率为90%,孔径150μm,拉伸强度>50MPa,三点抗弯强度>90MPa,特性黏度1.6dL/g(氯仿溶剂)。动物切口均于1～2周Ⅰ期愈合,动物饮食及活动恢复正常,无肢体活动受限及跛行。两种接骨板均固定牢固,骨折端无移位,材料逐步降解,实验组接骨板降解较对照组快。X线片:实验组术后2、4、8及12周骨折修复的X线阻射密度值分别为39.22±2.48、48.79±1.26、63.78±1.78及78.60±1.25;对照组分别为33.83±1.13、41.28±1.25、55.23±0.68及66.54±1.33,两组各时间点比较,差异均有统计学意义(P<0.01)。组织学观察,实验组接骨板与周围组织的相容性、成骨速度、骨再生量、再生髓腔结构等方面均优于对照组;实验组术后2、4、8及12周骨缺损区新骨形成面积百分比分别为0.106%±0.015%、0.292%±0.019%、0.457%±0.048%及0.601%±0.037%;对照组分别为0、0.193%±0.019%、0.339%±0.029%及0.574%±0.047%;不同时间点两组比较差异均有统计学意义(P<0.05)。结论复合rhBMP-2的PDLLA接骨板生物相容性良好,较之普通PDLLA接骨板具有更良好骨诱导性和骨折修复能力。
Objective To investigate the manufacture and biocompatibility of a bioabsorbable poly-D,L-lactic acid （PDLLA） plate containing rhBMP-2. Methods rhBMpo2 was composited with PDLLA （0.05 mg/plate） through vacuum to prepare PDLLA plate containing rhBMP-2. Thirty-two New Zealand rabbits （male or female） weighted （3.0 ±0.5） kg were used in the study. A 2.5 mm middle ulna osteotomy was made bilaterally. The bones as well as periosteum were removed. The right side of aU the animals was experimental side （n=32）, was fixed internally by PDLLA plate containing rhBMP-2.The left side ofaU the animals was control side （n=32）, was fixed by common PDLLA plate. After a follow-up of 2, 4, 8 and 12 weeks, the ulnas were examined visuaUy, radiographicaUy, histologicaUy, and by computer graph analysis to compare the biocompatibility. Results Porosity of PDLLA plate containing rhBMP-2 was 90%, aperture was 150μm, tensile strength was higher than 50 MPa, three point flexural strength was higher than 90 MPa and intrinsic viscosity was 1.6 dL/g （chloroform solvent）. All animals had a good healing 1 or 2 weeks after operation. All the animal＇s diet and movement were normal. All the fractures were stable. The plates in the experimental group degraded faster than those in the control group. Relative values of callus density evaluated by X-ray at 2, 4, 8 and 12 weeks after operation in the experimental group were 39.22 ± 2.48, 48.79 ± 1.26, 63.78 ± 1.78 and 78.60 ± 1.25 respectively. Those in the control defects were 33.83 ± 1.13, 41.28 ± 1.25, 55.23± 0.68 and 66.54 _± 1.33. At each time point, the experimental side produced better and more trabeculae than the control side did （P 〈 0.01）. Histological examination showed that the new bone formation in the experimental side at 2, 4, 8 and 12 weeks after operation was 0.106% ± 0.015%, 0.292% ± 0.019%, 0.457% ± 0.048% and 0.601% ± 0.037%, while those in the control side was 0.193% ± 0.019%, 0.339% ± 0.029% and 0.574% ± 0.047% respectively. At each time point, the experimental side produced better new bone formation than the control side did （P 〈 0.05）. The experimental side showed better compatibility between plates and surrounding tissue, faster bone formation, more bone regeneration mass and better medullary canal structure than the control side. Conclusion PDLLA plate containing rhBMP-2 has good biocompatibility and osteoinducibility to enhance fracture healing.
出处
《中国修复重建外科杂志》
CAS
CSCD
北大核心
2008年第2期173-177,共5页
Chinese Journal of Reparative and Reconstructive Surgery
基金
上海市卫生局青年科研基金资助项目(034y14)~~
