A bioactive glass functional hydrogel enhances bone augmentation via synergistic angiogenesis, self-swelling and osteogenesis

Bone augmentation materials usually cannot provide enough new bone for dental implants due to the material degradation and mucosal pressure. The use of hydrogels with self-swelling properties may provide a higher bone augmentation, although swelling is generally considered to be a disadvantage in tissue engineering. Herein, a double-crosslinked gelatin-hyaluronic acid hydrogels (GH) with self-swelling properties were utilized. Meanwhile, niobium doped bioactive glasses (NbBG) was dispersed in the hydrogel network to prepare the GH-NbBG hydrogel. The composite hydrogel exhibited excellent biocompatibility and the addition of NbBG significantly improved the mechanical properties of the hydrogel. In vivo results found that GH-NbBG synergistically promoted angiogenesis and increased bone augmentation by self-swelling at the early stage of implantation. In addition, at the late stage after implantation, GH-NbBG significantly promoted new bone formation by activating RUNX2/Bglap signaling pathway. Therefore, this study reverses the self-swelling disadvantage of hydrogels into advantage and provides novel ideas for the application of hydrogels in bone augmentation.