Dose-dependent enhancement of octacalcium phosphate biodegradation with gelatin matrix during bone regeneration in a rabbit tibial defect model
Dose-dependent enhancement of octacalcium phosphate biodegradation with gelatin matrix during bone regeneration in a rabbit tibial defect model
复制标题
兔胫骨缺损模型骨再生过程中明胶基质对磷酸八钙生物降解的剂量依赖性增强
作者：
K Saito;T Anada;Y Shiwaku;S Chiba;N Miyatake;K Suzuki;K Tsuchiya;O Suzuki
本研究旨在探讨明胶（Gel）基质中颗粒磷酸八钙（OCP）的剂量如何影响其在兔胫骨骨缺损中的骨再生和生物降解性能，该骨缺损深度为7 mm，直径为6 mm，位于皮质骨至骨髓间隙中。通过将直径为300-500 μm的OCP颗粒混合在含有17- 77wt%OCP的明胶基质中来制备对应于缺陷形状的海绵状OCP/凝胶棒。进行冻干和去水热处理以使材料交联。采用扫描电子显微镜、X射线衍射和傅里叶变换红外光谱对OCP/Gel复合材料进行了表征。植入后4周和6周，拍摄软X线片和显微CT，然后使用脱钙标本进行组织形态计量学分析。结果表明，复合材料具有直径达500 μm的多孔结构，且无论其在明胶基质中的含量如何，复合材料均保持OCP结构。OCP/Gel复合材料中OCP含量越高，骨再生能力越强，在皮质骨和骨髓区域的生物降解速度越快。这些结果表明，OCP含量的增加可以加快复合材料的生物降解趋势。这可能是由于OCP与明胶基质的作用，导致更高的骨传导性。
The present study was designed to investigate how the dose of granular octacalcium phosphate (OCP) in a gelatin (Gel) matrix affects its bone regenerative and biodegradable properties in a rabbit tibia defect with a depth of 7 mm and diameter of 6 mm made in the cortical bone to bone marrow space. A spongy OCP/Gel rod, which corresponded to the defect shape, was prepared by mixing OCP granules with diameters of 300–500 μm in a gelatin matrix that contained 17–77 wt% OCP. Lyophilization and dehydrothermal treatment were performed to cross-link the materials. OCP/Gel composites were characterized by scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. At 4 and 6 weeks after the implantation, soft X-ray and micro-CT were taken, followed by histomorphometric analysis using decalcified specimens. The results showed that the composites had a porous structure of up to 500 μm in diameter and maintained the OCP structure regardless of its content in the gelatin matrix. The OCP/Gel composite with a higher OCP content showed greater bone regeneration and tended to undergo faster biodegradation in both cortical bone and bone marrow regions. These results suggest that the biodegradation tendency of the composite could be accelerated by increasing the OCP content. This is likely due to the effect of OCP together with gelatin matrix, which results in higher osteoconductivity.