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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. [ABSTRACT FROM AUTHOR]

Polymeric vascular bioresorbable stents (BRSs) have been widely used for the treatment of coronary artery diseases. While additive manufacturing (AM) is changing the landscape of the healthcare sector by enabling the realization of patient‐specific stents with highly complex structures. There are, however, challenges associated with the use of polymeric BRS, particularly in‐stent restenosis (ISR), related to its poor mechanical properties. Therefore, the aim of this review is to provide an overview of recent advancements in the development of polymeric BRSs designed to meet both mechanical and biological requirements. First, biopolymers as well as shape memory polymers (SMPs) that are suitable for BRSs are highlighted and briefly described. Second, different types of designing structures of vascular stents in addition to introducing effective mechanical metamaterials, e.g., negative Poisson ratio (NPR) structures are addressed. Subsequently, AM methods currently being used to fabricate polymeric BRSs, are discussed and compared with conventional fabrication methods. Lastly, future directions for research are proposed in relation to existing challenges to the realization of a new generation of AM BRSs. Overall, this paper serves as a benchmark for future cardiovascular applications, especially in order to obtain clinically viable polymeric vascular stents by selecting suitable polymers, designs, and AM technologies. [ABSTRACT FROM AUTHOR]