Abstract：
The treatment of large craniofacial bone defects requires more advanced and effective strategies than bone grafts since such defects are challenging and cannot heal without intervention. In this regard, 3D printing offers promising solutions through the fabrication of scaffolds with the required shape, porosity, and various biomaterials suitable for specific tissues. In this study, 3D-printed polycaprolactone (PCL)-based scaffolds containing up to 30 % tricalcium silicate (TCS) were fabricated and then modified by incorporation of decellularized bone matrix- oxidized sodium alginate (DBM-OA). The results showed that the addition of 20 % TCS increased compressive modulus by 4.5-fold, yield strength by 12-fold, and toughness by 15-fold compared to pure PCL. In addition, the samples containing TCS revealed the formation of crystalline phases with a Ca/P ratio near that of hydroxyapatite (1.67). Cellular experiment results demonstrated that TCS have improved the biocompatibility of PCL-based scaffolds. On day 7, the scaffolds modified with DBM and 20 % TCS exhibited 8-fold enhancement of ALP activity of placenta-derived mesenchymal stem/stromal cells (P-MSCs) compared to pure PCL scaffolds. The present study\'s results suggest that the incorporation of TCS and DBM-OA into the PCL-based scaffold improves its mechanical behavior, bioactivity, biocompatibility, and promotes mineralization and early osteogenic activity.
摘要：
大型颅面骨缺损的治疗需要比骨移植物更先进和有效的策略，因为这种缺损具有挑战性，并且在没有干预的情况下无法愈合。在这方面,3D打印通过制造具有所需形状的支架提供了有希望的解决方案，孔隙度,和适用于特定组织的各种生物材料。在这项研究中,制造包含高达30%的硅酸三钙(TCS)的基于3D打印的聚己内酯(PCL)的支架,然后通过掺入脱细胞化的骨基质氧化的海藻酸钠(DBM-OA)来改性。结果表明,添加20%TCS可使压缩模量提高4.5倍,屈服强度提高12倍，与纯PCL相比，韧性提高了15倍。此外,含有TCS的样品显示形成了Ca/P比接近羟基磷灰石（1.67）的结晶相。细胞实验结果表明，TCS改善了PCL基支架的生物相容性。在第7天,与纯PCL支架相比,用DBM和20%TCS修饰的支架显示胎盘来源的间充质干细胞/基质细胞(P-MSC)的ALP活性增强8倍。本研究的结果表明，将TCS和DBM-OA掺入PCL基支架可改善其力学行为，生物活性，生物相容性，并促进矿化和早期成骨活性。
