Center of Dental Medicine, Institute of Oral Biotechnology & Bioengineering, University of Zurich, Zurich, Switzerland.
CABMM, Center for Applied Biotechnology and Molecular Medicine, University of Zurich, Zurich, Switzerland.
Tissue Eng Part A. 2023 Oct;29(19-20):507-517. doi: 10.1089/ten.TEA.2023.0033. Epub 2023 Jun 19.
Triply periodic minimal surfaces (TPMSs) are found to be promising microarchitectures for bone substitutes owing to their low weight and superior mechanical characteristics. However, existing studies on their application are incomplete because they focus solely on biomechanical or aspects. Hardly any studies where different TPMS microarchitectures are compared have been reported. Therefore, we produced hydroxyapatite-based scaffolds with three types of TPMS microarchitectures, namely Diamond, Gyroid, and Primitive, and compared them with an established Lattice microarchitecture by mechanical testing, 3D-cell culture, and implantation. Common to all four microarchitectures was the minimal constriction of a sphere of 0.8 mm in diameter, which earlier was found superior in Lattice microarchitectures. Scanning by μCT revealed the precision and reproducibility of our printing method. The mechanical analysis showed significantly higher compression strength for Gyroid and Diamond samples compared with Primitive and Lattice. After culture with human bone marrow stromal cells in control or osteogenic medium, no differences between these microarchitectures were observed. However, from the TPMS microarchitectures, Diamond- and Gyroid-based scaffolds showed the highest bone ingrowth and bone-to-implant contact . Therefore, Diamond and Gyroid designs appear to be the most promising TPMS-type microarchitectures for scaffolds produced for bone tissue engineering and regenerative medicine. Impact Statement Extensive bone defects require the application of bone grafts. To match the existing requirements, scaffolds based on triply periodic minimal surface (TPMS)-based microarchitectures could be used as bone substitutes. This work is dedicated to the investigation of mechanical and osteoconductive properties of TPMS-based scaffolds to determine the influencing factors on differences in their behavior and choose the most promising design to be used in bone tissue engineering.
三重周期性极小曲面 (TPMS) 因其重量轻和卓越的机械特性而被发现是有前途的骨替代物的微观结构。然而，由于它们仅专注于生物力学或方面，因此对其应用的现有研究并不完整。几乎没有报道过对不同 TPMS 微观结构进行比较的研究。因此，我们通过机械测试、3D 细胞培养和植入物比较，用三种类型的 TPMS 微观结构（金刚石、Gyroid 和原始）生产了基于羟基磷灰石的支架，并与已建立的晶格微观结构进行了比较。所有四种微观结构的共同点是最小直径为 0.8mm 的球体的最小收缩，这在以前的晶格微观结构中被发现是优越的。μCT 扫描显示了我们打印方法的精度和可重复性。机械分析表明，Gyroid 和 Diamond 样品的压缩强度明显高于原始和晶格。在对照或成骨培养基中与骨髓基质细胞共培养后，这些微观结构之间没有差异。然而，从 TPMS 微观结构来看，基于 Diamond 和 Gyroid 的支架显示出最高的骨向内生长和骨与植入物接触。因此，对于用于骨组织工程和再生医学的支架，Diamond 和 Gyroid 设计似乎是最有前途的 TPMS 型微观结构。
影响陈述大量的骨缺损需要应用骨移植物。为了满足现有要求，基于三重周期性极小曲面 (TPMS) 的微观结构的支架可以用作骨替代物。这项工作致力于研究基于 TPMS 的支架的机械和骨诱导特性，以确定影响其行为差异的因素，并选择最有前途的设计用于骨组织工程。
