In this study, we describe the additive manufacturing of porous three-dimensionally (3D) printed ceramic scaffolds prepared with hydroxyapatite (HA), β-tricalcium phosphate (β-TCP), or the combination of both with an extrusion-based process. The scaffolds were printed using a novel ceramic-based ink with reproducible printability and storability properties. After sintering at 1200°C, the scaffolds were characterized in terms of structure, mechanical properties, and dissolution in aqueous medium. Microcomputed tomography and scanning electron microscopy analyses revealed that the structure of the scaffolds, and more specifically, pore size, porosity, and isotropic dimensions were not significantly affected by the sintering process, resulting in scaffolds that closely replicate the original dimensions of the 3D model design. The mechanical properties of the sintered scaffolds were in the range of human trabecular bone for all compositions. All ceramic bioinks showed consistent printability over a span of 14 days, demonstrating the short-term storability of the formulations. Finally, the mass loss did not vary among the evaluated compositions over a period of 28 days except in the case of β-TCP scaffolds, in which the structural integrity was significantly affected after 28 days of incubation in phosphate-buffered saline. In conclusion, this study demonstrates the development of storable ceramic inks for the 3D printing of scaffolds of HA, β-TCP, and mixtures thereof with high fidelity and low shrinkage following sintering that could potentially be used for bone tissue engineering in load-bearing applications.

中文翻译：

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使用可存储陶瓷油墨的多孔支架的三维挤出印刷。

在这项研究中，我们描述了用羟基磷灰石（HA），β-磷酸三钙（β-TCP）或两者结合与基于挤出的工艺制备的多孔三维（3D）印刷陶瓷支架的增材制造。使用具有可再现的可印刷性和可存储性的新型陶瓷基油墨印刷支架。在1200℃下烧结后，根据结构，机械性能和在水性介质中的溶解来表征支架。微型计算机断层扫描和扫描电子显微镜分析显示，烧结过程并未显着影响支架的结构，尤其是孔径，孔隙率和各向同性尺寸，从而使支架紧密复制3D模型设计的原始尺寸。对于所有组合物，烧结支架的机械性能均在人小梁骨的范围内。所有陶瓷生物墨水在14天的时间里都显示出一致的可印刷性，表明了该制剂的短期可存储性。最后，除β-TCP支架外，在28天的时间内，所评估的组合物的质量损失没有变化，其中β-TCP支架在磷酸盐缓冲盐水中培养28天后，其结构完整性受到显着影响。总而言之，这项研究证明了可储存陶瓷油墨的开发，用于3D打印HA，β-TCP及其在烧结后具有高保真度和低收缩率的支架的混合物，这些混合物可潜在地用于承重应用中的骨组织工程。