Hayashi Koichiro, Yanagisawa Toshiki, Kishida Ryo, Tsuchiya Akira, Ishikawa Kunio
Department of Biomaterials, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi Higashi-ku, Fukuoka 812-8582, Japan.
Comput Struct Biotechnol J. 2023 Apr 5;21:2514-2523. doi: 10.1016/j.csbj.2023.03.053. eCollection 2023.
Synthetic bone grafts are in high demand owing to increased age-related bone disorders in the global aging population. Here, we report fabrication of gear-shaped granules (G-GRNs) for rapid bone healing. G-GRNs possessed six protrusions and a hexagonal macropore in the granular center. These were composed of carbonate apatite, i.e., bone mineral, microspheres with ∼1-μm micropores in the spaces between the microspheres. G-GRNs formed new bone and blood vessels (both on the granular surface and within the macropores) 4 weeks after implantation in the rabbit femur defects. The formed bone structure was similar to that of cancellous bone. The bone percentage in the defect recovered to that in a normal rabbit femur at week-4 post-implantation, and the bone percentage remained constant for the following 8 weeks. Throughout the entire period, the bone percentage in the G-GRN-implanted group was ∼10% higher than that of the group implanted with conventional carbonate apatite granules. Furthermore, a portion of the G-GRNs resorbed at week-4, and resorption continued for the following 8 weeks. Thus, G-GRNs are involved in bone remodeling and are gradually replaced with new bone while maintaining a suitable bone level. These findings provide a basis for the design and fabrication of synthetic bone grafts for achieving rapid bone regeneration.
由于全球老龄化人口中与年龄相关的骨疾病增多，合成骨移植材料的需求很高。在此，我们报告了用于快速骨愈合的齿轮状颗粒（G-GRNs）的制备。G-GRNs具有六个突起，颗粒中心有一个六边形大孔。它们由碳酸盐磷灰石，即骨矿物质，以及微球之间具有约1μm微孔的微球组成。G-GRNs在植入兔股骨缺损4周后在颗粒表面和大孔内形成了新骨和血管。形成的骨结构与松质骨相似。植入后第4周缺损处的骨百分比恢复到正常兔股骨的水平，并且在接下来的8周内骨百分比保持恒定。在整个期间，植入G-GRNs组的骨百分比比植入传统碳酸盐磷灰石颗粒组高约10%。此外，一部分G-GRNs在第4周时吸收，并且在接下来的8周内吸收持续。因此，G-GRNs参与骨重塑，并在维持合适骨水平的同时逐渐被新骨替代。这些发现为设计和制造用于实现快速骨再生的合成骨移植材料提供了基础。
