Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska, United States.
Center of Nanotechnology, King Abdulaziz University, Jeddah, Saudi Arabia.
Acta Biomater. 2021 Jun;127:313-326. doi: 10.1016/j.actbio.2021.03.009. Epub 2021 Mar 8.
Bone defects are commonly caused by traumatic injuries and tumor removal and critically sized defects overwhelm the regenerative capacity of the native tissue. Reparative strategies such as auto, xeno, and allografts have proven to be insufficient to reconstruct and regenerate these defects. For the first time, we introduce the use of handheld melt spun three dimensional printers that can deposit materials directly within the defect site to properly fill the cavity and form free-standing scaffolds. Engineered composite filaments were generated from poly(caprolactone) (PCL) doped with zinc oxide nanoparticles and hydroxyapatite microparticles. The use of PCL-based materials allowed low-temperature printing to avoid overheating of the surrounding tissues. The in situ printed scaffolds showed moderate adhesion to wet bone tissue, which can prevent scaffold dislocation. The printed scaffolds showed to be osteoconductive and supported the osteodifferentiation of mesenchymal stem cells. Biocompatibility of the scaffolds upon in vivo printing subcutaneously in mice showed promising results. STATEMENT OF SIGNIFICANCE.
骨缺损通常由创伤和肿瘤切除引起，临界大小的缺损会超过天然组织的再生能力。修复策略，如自体、异种和同种异体移植物，已被证明不足以重建和再生这些缺陷。我们首次引入手持式熔融纺丝三维打印机，该打印机可以直接在缺陷部位沉积材料，以正确填充腔并形成独立的支架。工程复合纤维由聚己内酯（PCL）掺杂氧化锌纳米粒子和羟基磷灰石微粒子制成。使用基于 PCL 的材料允许低温打印，以避免周围组织过热。原位打印的支架与湿骨组织具有适度的附着力，可以防止支架移位。打印的支架具有成骨作用，并支持间充质干细胞的成骨分化。在小鼠皮下体内打印时，支架的生物相容性显示出有希望的结果。
