Millions of procedures involving bone grafts and bone substitutes are performed worldwide each year. Traditional bone repair strategies include autograft, allograft, and surgical reconstruction, but they can carry potential risks of donor site morbidity, rejection, risk of disease transmission, and repeated surgery. The need for bone grafts in clinical practice continues to grow due to the increasing number of bone defects caused by trauma, cancer, infection and arthritis. Bone tissue engineering provides promising substitutes in biopharmaceutical applications. Chitosan has good biocompatibility, biodegradability, antibacterial, antioxidant, low toxicity and low cost, which is considered as an important bone repair material in the field of tissue regeneration. Thus, chitosan-based injectable hydrogels can uniformly fill irregular bone defects and have proven to be effective substitutes for autologous bone and dental implants when combined with other polymers or bioactive ingredients. This review focuses on the preparation, physicochemical properties and development status of chitosan-based injectable hydrogels in bone regeneration, and also summarizes the current challenges and future development direction of bone tissue engineering, which will provide a new idea for the development of a new generation of tissue engineering scaffold materials for the treatment of bone defect repair. |