纳米羟基磷灰石-聚羟基丁酸戊酯/聚乙二醇人工骨对骨缺损修复的作用*

背景：为改善羟基磷灰石强度低、韧性差的缺点，尝试将具有良好机械性能的聚羟基丁酸戊酯和高亲水性材料聚乙二醇与之共混制备复合材料。 目的：评价纳米羟基磷灰石-聚羟基丁酸戊酯/聚乙二醇（Nano-HA-PHBV/PEG）人工骨对骨缺损的修复作用，并与单纯纳米羟基磷灰石人工骨相比较。 设计、时间及地点：对比分析，体内动物实验，于2007-06/2008-05在南方医科大学珠江医院中心实验室及生物力学实验室完成。 材料：自制纳米羟基磷灰石人工骨和Nano-HA-PHBV/PEG人工骨。 方法：将30只新西兰兔双侧桡骨中段制成15 mm节段性骨缺损，左侧植入Nano-HA-PHBV/PEG人工骨为实验组，右侧植入纳米羟基磷灰石人工骨为对照组。 主要观察指标：X射线片观察骨缺损修复及材料降解情况；术后2，4，8，16，24周分别处死6只兔子取材，用骨密度测量仪测量缺损修复区骨密度；术后4，8，16，24周在骨密度测试结束后切取完整桡骨标本，行三点抗弯试验测量弯曲强度。 结果：X射线显示4周后两组骨缺损处植入材料均有不同程度的降解，骨缺损处均有新骨形成；实验组新骨密度在材料植入8周后开始高于对照组(P < 0.05)；16，24周时实验组桡骨弯曲强度高于对照组(P < 0.05)。 结论：Nano-HA-PHBV/PEG人工骨具有良好的成骨能力和生物相容性，其成骨能力优于单纯纳米羟基磷灰石人工骨。

Nano-hydroxyapatite-polyhydroxybutyrate valerate/polyethylene glycol artificial bone in bone defect repair

BACKGROUND: Hydroxyapatite (HA) is weak in the intensity, so polyhydroxybutyrate valerate (PHBV) that has well mechanical property and highly hydrophilic polyethylene glycol (PEG) are added to HA. OBJECTIVE: To evaluate the ability of Nano-HA-PHBV/PEG artificial bone in repairing the bone defect, and to compare with pure Nano-HA artificial bone. DESIGN, TIME AND SETTING: From June 2007 to May 2008 an in vivo randomized controlled animal experiment was performed at the Laboratory of Medical Biomechanics and Center Laboratory of Zhujiang Hospital, Southern Medical University. MATERIALS: Self-made Nano-HA and Nano-HA-PHBV/PEG artificial bone. METHODS: Thirty New Zealand white rabbits were used to induce 15-mm radius segmental defects. Composite Nano-HA-PHBV/PEG artificial bone was implanted on the left bone defect (experimental group), while Nano-HA artificial bone was implanted on the right bone defect (control group). MAIN OUTCOME MEASURES: X- ray examination was performed to observe the repair of bone defect and material degradation; Six rabbits were killed to measure the bone density at the defect area at 2, 4, 8, 16 and 24 weeks respectively; Radial bone was sampled at 4, 8, 16 and 24 weeks to measure the radius bending strength after bone density was measured. RESULTS: X-ray photography showed that there were material degradation and new bone formation at bone defect area in two groups after 4 weeks; The new bone density in experimental group was higher than control group after 8 weeks (P < 0.05). The radius bending strength of experimental group was higher than control group at 16 and 24 weeks (P < 0.05). CONCLUSION: The Nano-HA-PHBV/PEG artificial bone is favorable than Nano-HA in the bone formation ability and biocompatibility in the repair of bone defect.