Zhang Qing, Sun Changning, Zheng Jibao, Wang Ling, Liu Chaozong, Li Dichen
State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi'an Jiaotong University, 710054, Xi'an, ShaanXi, China; National Medical Products Administration (NMPA) Key Laboratory for Research and Evaluation of Additive Manufacturing Medical Devices, Xi'an Jiaotong University, 710054, Xi'an, ShaanXi, China; Centre for Medical Device Evaluation, National Medical Products Administration (NMPA), 100081, Beijing, China.
State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi'an Jiaotong University, 710054, Xi'an, ShaanXi, China; National Medical Products Administration (NMPA) Key Laboratory for Research and Evaluation of Additive Manufacturing Medical Devices, Xi'an Jiaotong University, 710054, Xi'an, ShaanXi, China; National Innovation Platform (Centre) for Industry-Education Integration of Medical Technology, Xi'an Jiaotong University, 710115, Xi'an, ShaanXi, China.
J Mech Behav Biomed Mater. 2025 Mar;163:106848. doi: 10.1016/j.jmbbm.2024.106848. Epub 2024 Dec 2.
Polyether-ether-ketone (PEEK) composites represent one of the most promising approaches to overcoming the weak osseointegration associated with the bioinertness of PEEK, making them highly suitable for clinical translation. Implants with porous structures fabricated by additive manufacturing offer the potential for long-term stability by promoting bone ingrowth. However, despite the importance of porous design, there is still no consensus on the optimal approach for PEEK-based composites. Given the significance of permeability and mechanical properties as functional indicators closely linked to osseointegration, the effects of material composition, structural design, and manufacturing processes on the permeability and mechanical properties of PEEK/hydroxyapatite (HA) scaffolds were systematically investigated in this study. In terms of permeability, the axial permeability of scaffolds with different pore sizes and representative volume elements varied within the range of 0.3-24.8 × 10 m. Among scaffolds with similar relative density, the Gyroid structure exhibited the lowest permeability, while the orthogonal structure demonstrated the highest. For cylindrical scaffolds, circumferential permeability decreased with increasing penetration depth, suggesting a potential reduction in bone ingrowth speed with depth. As for mechanical properties, the experimentally determined effective elastic modulus and effective yield strength of the scaffolds ranged from 675.1 MPa to 65.2 MPa and 43.5 MPa to 4.1 MPa, respectively. The permeability and mechanical properties of PEEK/HA scaffolds with relative density ranging from 35% to 50% were aligned with the those of human cancellous bone. Heat treatment at 240 °C for 120 min increased the crystallinity of PEEK to 37.2%, resulting in a substantial improvement in both the strength and stiffness of the scaffolds. However, excessive crystallinity led to brittle fracture, which in turn reduced the strength of the scaffolds. This study employed a systematic research approach to investigate how material composition, structural design, and manufacturing processes influence the mechanical properties and permeability of PEEK composite bone scaffolds, which are crucial for bone ingrowth. The results offered insights that support the design, manufacturing, and performance evaluation of PEEK-based porous implants.
聚醚醚酮（PEEK）复合材料是克服与PEEK生物惰性相关的骨整合不足问题最具前景的方法之一，这使其非常适合临床应用。通过增材制造制备的具有多孔结构的植入物可通过促进骨长入来实现长期稳定性。然而，尽管多孔设计很重要，但对于基于PEEK的复合材料的最佳方法仍未达成共识。鉴于渗透率和力学性能作为与骨整合密切相关的功能指标的重要性，本研究系统地研究了材料组成、结构设计和制造工艺对PEEK/羟基磷灰石（HA）支架的渗透率和力学性能的影响。在渗透率方面，不同孔径和代表性体积单元的支架的轴向渗透率在0.3 - 24.8×10⁻¹⁵ m范围内变化。在具有相似相对密度的支架中，Gyroid结构的渗透率最低，而正交结构的渗透率最高。对于圆柱形支架，周向渗透率随穿透深度的增加而降低，这表明骨长入速度可能随深度而降低。至于力学性能，实验测定的支架的有效弹性模量和有效屈服强度分别为675.1 MPa至65.2 MPa和43.5 MPa至4.1 MPa。相对密度在35%至50%之间的PEEK/HA支架的渗透率和力学性能与人体松质骨的渗透率和力学性能一致。在240°C下热处理120分钟可使PEEK的结晶度提高到37.2%，从而使支架的强度和刚度都有显著提高。然而，过高的结晶度会导致脆性断裂，进而降低支架的强度。本研究采用系统的研究方法来研究材料组成、结构设计和制造工艺如何影响PEEK复合骨支架的力学性能和渗透率，这些对于骨长入至关重要。研究结果为基于PEEK的多孔植入物的设计、制造和性能评估提供了参考。
