Bone tissue is composed of organic minerals and cells. It has the capacity to heal for certain minor damages, but when the bone defects surpass the critical threshold, they need fixing. Bone regeneration through natural and synthetic biodegradable materials requires various steps, such as manufacturing methods and materials selection. A successful biodegradable bone graft should have a high surface area/ volume ratio, strength, and a biocompatible, porous structure capable of promoting cell adhesion, proliferation, and differentiation. Considering these requirements, the electrospinning technique is promising for creating functional nano-sized scaffolds. The multi-axial methods, such as coaxial and triaxial electrospinning, are the most popular techniques to produce double or tri-layered scaffolds, respectively. Recently, stem cell culture on scaffolds and the application of osteogenic differentiation protocols on these scaffolds have opened new possibilities in the field of biomaterials research. This review discusses an overview of the progress in coaxial and triaxial technology through biodegradable composite bone materials. The review also carefully elaborates the osteogenic differentiation using stem cells and their performance with nano-sized scaffolds.

中文翻译：

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用于基于干细胞的骨再生的共轴和三轴静电纺丝

骨组织由有机矿物质和细胞组成。它有能力治愈某些轻微损伤，但当骨缺损超过临界阈值时，就需要修复。通过天然和合成的可生物降解材料进行骨再生需要多个步骤，例如制造方法和材料选择。成功的可生物降解骨移植物应具有高表面积/体积比、强度以及能够促进细胞粘附、增殖和分化的生物相容性多孔结构。考虑到这些要求，静电纺丝技术有望用于创建功能性纳米尺寸支架。多轴方法，例如同轴和三轴静电纺丝，分别是生产双层或三层支架的最流行的技术。最近，支架上的干细胞培养以及成骨分化方案在这些支架上的应用为生物材料研究领域开辟了新的可能性。本综述概述了可生物降解复合骨材料的同轴和三轴技术的进展。该评论还仔细阐述了使用干细胞的成骨分化及其在纳米尺寸支架上的性能。