负载纳米羟磷灰石的结冷胶修复大鼠下颌骨缺损的效果评价

目的: 观察负载纳米羟磷灰石的结冷胶（GG/nHA）修复大鼠下颌骨缺损的效果。方法: 于16只SD大鼠下颌骨制备直径为5 mm的临界骨缺损,随机分为2组,实验组骨缺损区注入GG/nHA,对照组骨缺损区填充可吸收性明胶海绵。术后4周、8周处死大鼠,以Micro-CT定量分析骨组织愈合情况。苏木精-伊红（H-E）染色和马松（Masson）染色定性评估骨组织修复情况。采用GraphPad Prism 8.0软件包对数据进行统计学分析。结果: 制备的GG/nHA具有良好的可注射性,可经注射器推出至骨缺损区。术后4周和8周,实验组缺损区的骨生成量及骨体积分数（BV/TV）均显著高于对照组（P<0.05）。H-E染色和Masson染色均见实验组较对照组有更多新骨形成。结论: GG/nHA可以注射形式注入下颌骨缺损区,促进其愈合,有望成为微创修复口腔颌面部骨缺损的新型材料。

Repair of mandibular defects with hydrogel loaded with nano-hydroxyapatite in rats

PURPOSE: To observe the effect of gellan gum loaded with nano-hydroxyapatite (GG/nHA) on repairing mandibular defect in rats. METHODS: Critical bone defects with 5 mm in diameter on the mandible of 16 SD rats were created and randomly divided into two groups. The bone defects in the experimental group were injected with GG/nHA and the control group were filled with absorbable gelatin sponge. The rats were sacrificed at 4 and 8 weeks after operation. The bone tissue healing was evaluated by Micro-CT. Bone tissue repairing effect was evaluated by hematoxylin-eosin (H-E) staining and Masson staining. GraphPad Prism 8.0 software package was used for statistical analysis. RESULTS: The prepared GG/nHA had a good injectability and could be delivered to the bone defect area with a syringe. Four and 8 weeks after operation, the newly formed bone and bone volume fraction (BV/TV) in the experimental group were higher than those in the control group, and the difference was statistically significant (P<0.05). Larger number of new bone were observed in the experimental group than the control group by H-E staining and Masson staining. CONCLUSIONS: GG/nHA can be injected into the mandibular defect area to promote its healing, and it is expected to be used as a novel bio-material for minimally invasive repair of oral and maxillofacial bone defects.