Wang Hui, Zhang Jiaxin, Bai Haotian, Wang Chenyu, Li Zuhao, Wang Zhonghan, Liu Qingping, Wang Zhenguo, Wang Xianggang, Zhu Xiujie, Liu Jiaqi, Wang Jincheng, Zhao Xin, Ren Luquan, Liu He
Department of Orthopaedics, The Second Hospital of Jilin University, Changchun 130041, China.
Department of Plastic & Reconstruct Surgery, First Hospital of Jilin University, Changchun 130061, China.
Biomater Adv. 2025 Feb;167:214092. doi: 10.1016/j.bioadv.2024.214092. Epub 2024 Oct 31.
Despite significant progress in repairing osteochondral injuries using 3D printing technology, most cartilage layer scaffolds are made of degradable materials, making it difficult to simultaneously provide extracellular matrix functionality while replicating the mechanical properties of natural cartilage layers. Additionally, their degradation rate is challenging to align with cartilage regeneration. Furthermore, double-layer scaffolds commonly used for repairing osteochondral often exhibit inadequate bonding between the cartilage layer scaffolds and bone layer scaffolds. To solve these problems, we presented a bilayer scaffold composed of a 3D printed non-degradable thermoplastic polyurethane (TPU) scaffold filled with hydrogel (Gel) made of gelatin and sodium alginate as the cartilage layer (noted as TPU/Gel), meanwhile, a 3D printed polylactic acid (PLA) scaffold containing 10 % hydroxyapatite (HA) as the bone layer (noted as PLA/HA). At the junction of the bone layer and cartilage layer, TPU tightly bonded with the bone layer scaffold under high temperatures. The hydrogel filling within the TPU layer of cartilage served not only to lubricate the joint surface but also aided in creating a 3D microenvironment. The non-degradable nature of TPU allowed the cartilage layer scaffold to seamlessly integrate with the surrounding regenerated cartilage, achieving permanent replacement and providing shock absorption and weight-bearing effects. This effectively addressed the mechanical challenges associated with cartilage regeneration and resolved the inconsistency between cartilage regeneration and material degradation rates.
尽管在使用3D打印技术修复骨软骨损伤方面取得了重大进展，但大多数软骨层支架由可降解材料制成，这使得在复制天然软骨层的机械性能的同时，难以同时提供细胞外基质功能。此外，它们的降解速率很难与软骨再生相匹配。此外，常用于修复骨软骨的双层支架在软骨层支架和骨层支架之间通常表现出结合不足。为了解决这些问题，我们提出了一种双层支架，由填充有由明胶和海藻酸钠制成的水凝胶（Gel）的3D打印不可降解热塑性聚氨酯（TPU）支架作为软骨层（记为TPU/Gel），同时，一种含有10%羟基磷灰石（HA）的3D打印聚乳酸（PLA）支架作为骨层（记为PLA/HA）。在骨层和软骨层的交界处，TPU在高温下与骨层支架紧密结合。软骨TPU层内填充的水凝胶不仅起到润滑关节表面的作用，还有助于创造一个3D微环境。TPU的不可降解性质使软骨层支架能够与周围再生软骨无缝整合，实现永久替代并提供减震和承重效果。这有效地解决了与软骨再生相关的机械挑战，并解决了软骨再生与材料降解速率之间的不一致问题。
