Kneadable dough-type hydrogel transforming from dynamic to rigid network to repair irregular bone defects
Ningtao Wang, Jie Chen, Yanyang Chen, Liang Chen, Luhan Bao, Zhengmei Huang, Zhengmei Huang, Xiaoyu Han, Jiangkuo Lu, Zhengwei Cai, Wenguo Cui, Zhengwei Huang, Zhengwei Huang
Abstract
Irregular bone defects, characterized by unpredictable size, shape, and depth, pose a major challenge to clinical treatment. Although various bone grafts are available, none can fully meet the repair needs of the defective area. Here, this study fabricates a dough-type hydrogel (DR-Net), in which the first dynamic network is generated by coordination between thiol groups and silver ions, thereby possessing kneadability to adapt to various irregular bone defects. The second rigid covalent network is formed through photocrosslinking, maintaining the osteogenic space under external forces and achieving a better match with the bone regeneration process. In vitro , an irregular alveolar bone defect is established in the fresh porcine mandible, and the dough-type hydrogel exhibits outstanding shape adaptability, perfectly matching the morphology of the bone defect. After photocuring, the storage modulus of the hydrogel increases 8.6 times, from 3.7 kPa (before irradiation) to 32 kPa (after irradiation). Furthermore, this hydrogel enables effective loading of P24 peptide, which potently accelerates bone repair in Sprague–Dawley (SD) rats with critical calvarial defects. Overall, the dough-type hydrogel with kneadability, space-maintaining capability, and osteogenic activity exhibits exceptional potential for clinical translation in treating irregular bone defects. Inspired by the kneadability of dough, a sequentially crosslinked dough-type hydrogel, DR-Net, is designed to repair irregular bone defects. The first dynamic network is formed by S–Ag coordination bonds, which makes the hydrogel kneadable to fill various bone defects. Subsequently, the second rigid network is constructed via in situ photocuring, enhancing mechanical properties to maintain the space for bone regeneration. • Inspired by the kneadability of dough, this study developed an innovative dough-type hydrogel for irregular bone defects. • This hydrogel can be kneaded to match various bone morphologies and achieve space maintenance via in situ photocuring. • This osteogenic dough-type hydrogel exhibits exceptional potential for clinical translation.