The regeneration of periodontal tissue defects remains a clinical challenge due to its complex tissue structure (e.g. periodontal ligament, alveolar bone and cementum) and poor self-healing ability. In situ tissue engineering has emerged as a promising approach that combines frameworks with growth factors that are specifically chosen for the recruitment of endogenous stem cells to the site of injury and to evoke the innate regenerative potential of the body. Herein, a core/shell fibrous super-assembled framework (SAF)-based sequential growth factor delivery system is developed, in which basic fibroblast growth factor (bFGF) and bone morphogenetic protein-2 (BMP-2) are designed to release in a sequential manner to facilitate in situ regeneration of the cementum-ligament-bone complex. The in situ tissue engineering framework (iTE-framework) shows ameliorated physicochemical properties and improved hydrophilicity, with an initial burst release of bFGF in the first few days, followed by a slow and constant release of BMP-2 up to 4 weeks. The iTE-framework shows excellent biocompatibility, significantly promoting the proliferation, migration and osteogenic differentiation of human periodontal ligament stem cells (PDLSCs) in vitro. After implantation in rat periodontal defects, the iTE-framework effectively triggers the recruitment of mesenchymal stem cells (MSCs) to the defect site, significantly promotes the formation of new bones, and facilitates the regeneration of the periodontal ligament and cementum tissue in vivo. Therefore, this sequential delivery system provides a promising therapeutic strategy for cementum-ligament-bone complex regeneration.

中文翻译：

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具有双重生长因子的超组装核/壳纤维骨架，用于原位牙骨质-韧带-骨复合物的再生。

牙周组织缺损的再生由于其复杂的组织结构（例如牙周韧带，牙槽骨和牙骨质）和较差的自我修复能力仍然是临床上的挑战。原位组织工程已经成为一种有前途的方法，该方法将框架与生长因子相结合，而生长因子是专门为将内源性干细胞募集至损伤部位并唤起人体固有的再生潜能而选择的。本文中，开发了基于核/壳纤维超组装框架（SAF）的连续生长因子递送系统，其中设计了基本成纤维细胞生长因子（bFGF）和骨形态发生蛋白2（BMP-2）释放顺序方式以促进牙骨质-韧带-骨复合物的原位再生。原位组织工程框架（iTE-framework）表现出改善的理化特性和改善的亲水性，在最初几天内bFGF首次爆发释放，随后长达4周缓慢而持续地释放BMP-2。iTE框架显示出出色的生物相容性，在体外显着促进人牙周膜干细胞（PDLSC）的增殖，迁移和成骨分化。植入大鼠牙周缺损后，iTE框架有效触发了间充质干细胞（MSC）募集到缺损部位，显着促进了新骨的形成，并促进了体内牙周膜和牙骨质组织的再生。因此，