Rationally designed meta-biomaterials present unprecedented combinations of mechanical, mass transport, and biological properties favorable for tissue regeneration. Here we introduce hybrid meta-biomaterials with rationally-distributed values of negative (auxetic) and positive Poisson's ratios, and use them to design meta-implants that unlike conventional implants do not retract from the bone under biomechanical loading. We rationally design and additively manufacture six different types of meta-biomaterials (three auxetic and three conventional), which then serve as the parent materials to six hybrid meta-biomaterials (with or without transitional regions). Both single and hybrid meta-biomaterials are mechanically tested to reveal their full-field strain distribution by digital image correlation. The best-performing hybrid meta-biomaterials are then selected for the design of meta-implants (hip stems), which are tested under simulated-implantation conditions. Full-field strain measurements clearly show that, under biomechanical loading, hybrid meta-implants press onto the bone on both the medial and lateral sides, thereby improving implant–bone contact and potentially implant longevity.

中文翻译：

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合理设计的异体植入物：生长激素和常规异体生物材料的组合†

合理设计的超生物材料呈现出前所未有的机械，大量运输和有利于组织再生的生物学特性的组合。在这里，我们介绍了具有合理分布的负（膨胀）和正泊松比值的混合超生物材料，并使用它们来设计与传统植入物不同的，在生物力学负荷下不会从骨骼中退回的超植入物。我们合理地设计和累加制造了六种不同类型的超生物材料（三种非生物材料和三种常规材料），然后将它们用作六种混合超生物材料（具有或不具有过渡区域）的母材。对单一和混合的超生物材料都进行了机械测试，以通过数字图像相关揭示其全场应变分布。然后选择性能最佳的混合生物材料来设计间位植入物（髋骨茎），并在模拟植入条件下对其进行测试。全场应变测量清楚地表明，在生物力学负荷下，混合型异种植入物在内侧和外侧均压在骨头上，从而改善了植入物与骨的接触并可能延长了植入物的寿命。