广东省重点领域研发计划项目( 2018B090906001),陕西省自然科学基础研究计划项目( 2022JQ- 378),中国博士后科学基金项目(2020M683458),国家重点研发计划项目(2018YFE0207900),国家自然科学基金项目(51835010),中央高校基本科研业务费,陕西高校青年创新团队,广东省基础与应用基础研究基金项目(2020B1515130002)
目的 针对材料挤出成形 3D 打印聚醚醚酮(polyetheretherketone, PEEK)骨替代物制造工艺存在明显各向异性的问题,以下肢股骨为例,研究不同摆放方式下 3D 打印 PEEK 股骨替代物的力学性能。 方法 在有限元模型中模拟人体步态周期中 5 种姿态,改变正交各向异性,计算不同打印摆放方式下股骨应力与变形,并通过力学实验研 究 3D 打印 PEEK 股骨的安全性与稳定性。 结果 竖直摆放优于水平摆放方式,此时 3D 打印 PEEK 股骨替代物最大应力为 46. 56 MPa,低于 PEEK 材料的屈服强度但变形量大于自然股骨,满足服役过程中力学性能需求,而承载稳定性有待提高。 结论 使用材料挤出成形制造承重骨时应优先采用竖直摆放的方式,3D 打印技术在用于承重 部位骨替代物时应谨慎考虑其各向异性对替代物服役性能的影响。
Objective Aiming at the problem of significant anisotropy in the three-dimensional ( 3D) printed polyether-ether-ketone ( PEEK) bone substitutes manufactured by material extrusion technology, taking the femur, the main load-bearing long bone of the lower limb, as an example, the biomechanical properties of the femoral model under different direction in the build chamber were evaluated by the combination of finite element analysis and in-vitro mechanical experiment. Methods A left femoral model was obtained by reconstruction from CT data. The stress and displacement of the 3D printed PEEK femur with different directions in the build chamber under five physiological postures in the human gait cycle were simulated by varying the orthogonal anisotropy mechanical properties. An in-vitro mechanical experiment was conducted to investigate the safety and stability of the femur through a 3D printed PEEK femur. Results When the long axis of the femur model was perpendicular to the building platform of the 3D printer, a better mechanical property was obtained, and the maximum von Mises stress was 46. 56 MPa, which was lower than the yield stress of PEEK, while the maximum displacement was larger than that of the natural femur under same loading condition. Therefore, the 3D printed PEEK femur met the strength requirement, but the stability needs to be improved. Conclusions The long axis is recommended to be perpendicular to the building platform when the material extrusion technology was used for the substitute of the load-bearing long bone, and the effect of its anisotropy on service performance of the substitute should be carefully considered when the 3D printing technology is used for load-bearing bone substitute.
姚思琦,孙畅宁,王 玲,石长全,李涤尘.聚醚醚酮各向异性 3D 打印对股骨替代物力学性能的影响[J].医用生物力学,2023,38(2):276-282复制