In Situ Bioprinting Enhances Bone Regeneration in a Live Animal Model with Craniofacial Defect.

In situ bioprinting represents an innovative approach in tissue engineering and regenerative medicine, enabling direct deposition of bioinks within the body to create or repair tissues at the target site. This technique leverages advanced bioprinting technologies to deliver cells, biomaterials, and bioactive molecules in a precise, controlled manner, offering the potential for on-demand tissue repair and minimizing the need for extensive surgical intervention. In this research, we apply for the first time in the literature a standard 3D bioprinter to perform in situ bioprinting over the bone defects of live animals under anesthesia and discuss the bone regeneration potential. For this, critical-sized bone defects were created on the parietal bones of the rabbits, followed by the application of autologous adipose-derived stem cell-laden bioink using a 3D bioprinter. Postoperative evaluations included micro-CT and histopathological analysis to assess bone healing and bone-material integration. The results demonstrated successful bone regeneration with the in situ bioprinting approach, as compared to the sham and the use of bioink-only. In conclusion, this study contributes to the growing body of evidence supporting in situ 3D bioprinting as a viable and promising technique for craniofacial bone regeneration, with potential implications for broader clinical relevance and paves the way for future clinical applications.