3D-PRINTED SUPERELASTIC LATTICE-BASED STRUCTURES FOR LOAD-BEARING BIOMEDICAL APPLICATIONS

用于承载生物医学应用的 3D 打印超弹性晶格结构

• 批准号: RGPIN-2020-05800
• 负责人: Brailovski, Vladimir
• 金额: $ 2.84万
• 依托单位: École de technologie supérieure
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=740837
• 关键词: 3D; PRINTED; SUPERELASTIC; LATTICE; BASED

The proposed research program aims at developing lattice-based implants with enhanced biomechanical compatibility and geometric conformity, by bridging the fields of biomechanics, mechanical design, materials science and technology. The application focus of this research program is intervertebral cages, since these devices play a significant role in the quality of life of patients with spinal disorders, and none of the currently available designs offers a satisfying solution. The applicant suggests that superelastic lattice-based implants with enhanced biomechanical and geometrical compatibilities will improve the outcome of implantation by optimizing the load sharing capacity of such devices and facilitating their installation. The development and ex vivo validation of a new generation of orthopedic implants constitute the main innovative aspects of this research. In order to mimic the behavior of surrounding bone, and maintain the mechanical strength of an implant, while providing adequate pore size for bone ingrowth, the project starts with the structural optimization and modeling of different lattice structure candidates. Next, these structures will be 3D-printed from a superelastic shape memory alloy and subjected to static and fatigue mechanical testing in order to establish scaling relations between the functional properties of cellular structures and their bulk material equivalents. To avoid the trial-and-error approach when optimizing these structures, their superelastic behavior will be simulated using a multi-scale numerical modeling approach, and the numerical results will be compared with the experimental observations. Next, intervertebral cage prototypes will be designed and tested to simulate physiological movements of the spine: compression, flexion/extension and axial rotation. Prototype cages will be retro-engineered to fit the intervertebral spaces in two typical locations (cervical and lumbar), using CT files obtained from patients. Finally, in the perspective of just-in-time implant delivery to the operation room, a technologically reliable and economically viable workflow will be developed. The body of knowledge created during this research will be directly transposable from intervertebral cages (application focus of this program) to other load-bearing personalized implant applications, namely, endoprostheses for the replacement of critical bone defects following bone tumors or invasive soft tissue sarcomas. Furthermore, a better understanding of the impact of the 3D printing technology on the service properties, especially with respect to fatigue, will be widely applicable, and will not be limited exclusively to shape memory alloys and the medical domain. Finally, the proposed program will contribute to the multidisciplinary (biomechanics, mechanical design, materials science, metallurgy) training of highly qualified personnel and attract top-level local and foreign students to ETS.

拟议的研究计划旨在通过桥接生物力学，机械设计，材料科学和技术的领域来开发具有增强生物力学兼容性和几何形状合规性的基于晶格的植入物。该研究计划的应用重点是椎间笼，因为这些设备在脊柱疾病患者的生活质量中起着重要作用，并且当前可用的设计都没有提供令人满意的解决方案。申请人认为，具有增强生物力学和几何兼容性的超弹性基于晶格的植入物将通过优化此类设备的负载共享能力并促进其安装来改善植入的结果。新一代骨科植入物的开发和实体验证构成了这项研究的主要创新方面。为了模仿周围骨骼的行为，并保持植入物的机械强度，同时为骨向内生长提供了足够的孔径，该项目始于不同晶格结构候选物的结构优化和建模。接下来，这些结构将从超弹性形状的存储合金中进行3D打印，并进行静态和疲劳机械测试，以建立细胞结构的功能性能与其块状材料等效物之间的缩放关系。为了避免在优化这些结构时进行试验方法，将使用多尺度数值建模方法对其超弹性行为进行模拟，并将数值结果与实验观察结果进行比较。 接下来，将设计和测试椎骨原型以模拟脊柱的生理运动：压缩，屈曲/延伸和轴向旋转。使用从患者获得的CT文件中，将重新设计原型笼子，以适合两个典型位置（宫颈和腰部）的椎间空间。最后，从及时植入物运送到操作室的角度来看，将开发出技术可靠且经济可行的工作流程。 在这项研究中创建的知识物体将直接从椎间笼（该程序的应用重点）直接转座，转换为其他承重的个性化植入物应用，即，内预本植物以替换骨骼肿瘤或侵入性软组织肉瘤后临界骨缺陷的临界骨缺陷。此外，对3D打印技术对服务属性的影响（尤其是在疲劳方面）的影响将是广泛适用的，并且不会仅限于塑造内存合金和医疗领域。最后，拟议的计划将为高素质人员的多学科（生物力学，机械设计，材料科学，冶金学）培训做出贡献，并吸引顶级本地和外国学生进入ETS。