骨支架在组织工程中起着至关重要的作用,特别是在促进自然修复不足的骨再生方面。尽管聚合物骨支架的制造取得了进展,挑战仍然是优化他们的机械弹性。具体来说,关于聚合物骨支架的疲劳行为的研究很少。这项研究调查了孔结构对准静态和循环压缩下聚乳酸(PLA)支架力学性能的影响。使用基于挤出的3D打印以各种设计制造孔隙率为60%的PLA支架:Gygior,Lidinoid,Fischer-Koch,IWP,和Voronoi.结果表明,甲状腺支架具有最高的抗压强度(6.6MPa),其次是Lidinoid,Fischer-Koch,IWP,和Voronoi设计。增加的支柱厚度与更高的压缩强度有关。然而,归一化抗疲劳性显示出不同的模式。虽然支架在低应变振幅下抵抗疲劳循环,在较高的应变下观察到疲劳损伤。Voronoi结构表现出最高的归一化疲劳性能,在85%应变幅度下持续约58,000次循环,其次是甲状腺,Fischer-Koch,Lidinoid,和IWP结构。与支架的最小横截面积相关的不同拓扑结构中的疲劳性能增强。考虑到静态强度和疲劳强度的重要性,甲状腺拓扑结构是整体的首选。
Bone scaffolds serve a crucial role in tissue engineering, particularly in facilitating bone regeneration where natural repair is insufficient. Despite advancements in the fabrication of polymeric bone scaffolds, the challenge remains to optimize their mechanical resilience. Specifically, research on the fatigue behaviour of polymeric bone scaffolds is scarce. This study investigates the influence of pore architecture on the mechanical performance of poly-lactic-acid (PLA) scaffolds under quasi-static and cyclic
compression. PLA scaffolds with a 60% porosity were fabricated using extrusion-based 3D printing in various designs: Gyroid, Lidinoid, Fischer-Koch, IWP, and Voronoi. Results demonstrated that Gyroid scaffolds had the highest compressive strength (6.6 MPa), followed by Lidinoid, Fischer-Koch, IWP, and Voronoi designs. Increased strut thickness was linked to higher compressive strength. However, normalized fatigue resistance showed a different pattern. While scaffolds resisted fatigue cycles at low strain amplitudes, fatigue damage was observed at higher strains. Voronoi structures exhibited the highest normalized fatigue performance, enduring around 58,000 cycles at 85% strain amplitude, followed by Gyroid, Fischer-Koch, Lidinoid, and IWP structures. Enhanced fatigue performance in different topologies correlated with the minimum cross-sectional area of scaffolds. Given the importance of both static and fatigue strength, the Gyroid topology emerges as the superior choice overall.