Data for: Evaluation of patient-specific cranial implant design using finite elemental analysis

This study aims to assess the load-bearing capacity of three patient-specific cranial implants. Although various studies exist that have analysed the mechanical behaviour of cranial implants, little attention is given to the design evaluation of a ceramic-titanium (CeTi) implant. The CeTi implant consists of a solid part in the centre of the implant and a scaffold at the border, both made of the Ti6Al4V-alloy. In the scaffold structure, HydroSet® is injected and sculpted. In order to better understand the mechanical behaviour of the CeTi implant, both tangential and axial screws are compared with a PEEK implant. Six computational models are developed in Abaqus/CAE. For each patient-specific implant, a global as well as a local model is constructed. The global models are subjected to two static loading conditions representing an impact load and the intracranial pressure. Nodal boundary conditions are imposed on the local models which represent the two aforementioned loading conditions. The global models are used to evaluate the location and magnitude of maximum Von Mises stress and displacement, whereas the local models offer the possibility to evaluate the Max Principal Stress in more detail. Hence, this work offers a broad view of the biomechanical properties of the cranial implants as different stress criteria are evaluated. Interaction properties are assigned between the cranial implant and neurocranium in order to mimic the biofidelic situation. Linear elastic and isotropic material properties are implemented for the various models. The results of the different analyses show that the PEEK cranial implant offers a less good brain and neurocranial protection due to its high flexibility and local peak stresses at the bone-screw interface. The CeTi implants are able to evenly distribute the stresses along the interface and thus reduce the risk for neurocranial fracture. The scaffold structure at the border of the implant reduces stress shielding and enhances bone ingrowth. Moreover, brain injuries are less likely to occur as the CeTi implant has a small deflection. The design evaluation presented in this work can further be used for design optimization purposes.本研究旨在评估三款患者专属（patient-specific）颅骨植入物的承载能力。尽管已有多项研究针对颅骨植入物的力学行为展开分析，但针对陶瓷钛（CeTi）植入物的设计评估却相对匮乏。该CeTi植入物由植入物中心的实体结构与边缘的支架结构构成，二者均采用Ti6Al4V合金制备；支架结构内部注入并成型HydroSet®材料。为进一步明晰CeTi植入物的力学行为，本研究将切向螺钉与轴向螺钉分别与聚醚醚酮（PEEK）植入物进行对比。研究团队在Abaqus/CAE中构建了六组计算模型：针对每一款患者专属植入物，分别搭建全局模型与局部模型。全局模型需承受两种静态加载工况，分别模拟冲击载荷与颅内压；局部模型则施加对应上述两种加载工况的节点边界条件。全局模型用于评估最大冯·米塞斯应力与位移的位置及幅值，而局部模型则可更细致地分析最大主应力。由此，本研究通过评估多种应力准则，全面展现了颅骨植入物的生物力学特性。为模拟真实生物环境，研究人员为颅骨植入物与神经颅之间赋予了交互属性，且所有模型均采用线弹性各向同性材料属性。不同分析的结果显示，PEEK颅骨植入物因柔韧性较强，且骨-螺钉界面处存在局部峰值应力，对颅脑与神经颅的防护效果欠佳。与之相比，CeTi植入物可将应力均匀分布于界面处，从而降低神经颅骨折的风险。植入物边缘的支架结构能够减少应力遮挡效应，并促进骨长入。此外，由于CeTi植入物的挠度较小，颅脑损伤的发生概率进一步降低。本研究提出的设计评估方法，可进一步应用于颅骨植入物的设计优化工作。