A technology to create a cell-seeded fibrin-based implant matching the size and shape of bone defect is required to create an anatomical implant. The aim of the study was to develop a technology of cell-seeded fibrin gel implant creation that has the same shape and size as the bone defect at the site of implantation. Using computed tomography (CT) images, molds representing bone defects were created by 3D printing. The form was filled with fibrin glue and human dental pulp stem cells (DPSC). The viability, set of surface markers and osteogenic differentiation of DPSC grown in fibrin gel along with the clot retraction time were evaluated. In mice, an alveolar bone defect was created. The defect was filled with fibrin gel seeded with mouse DPSC. After 28 days, the bone repair was analyzed with cone beam CT and by histological examination. The proliferation rate, set of surface antigens and osteogenic potential of cells grown inside the scaffold and in 2D conditions did not differ. In mice, both cell-free and mouse DPSC-seeded implants increased the bone tissue volume and vascularization. In mice with cell-seeded gel implants, the bone remodeling process was more prominent than in animals with a cell-free implant. The technology of 3D-printed forms for molding implants can be used to prepare implants using components that are not suitable for 3D printing.

Relevance. Creating three-dimensional scaffolds from biodegradable materials and seeding them with stem cells derived from the oral tissues is a promising tool for guided tissue regeneration. Pulp and periodontal stem cells have a high potential for osteogenic differentiation, which biologically determines their use in surgical bone reconstruction. The experiment shows the result of using fibrin glue seeded with pulp and periodontal stem cells on the mandible of laboratory mice. The article presents the results of computed tomography and histological examination. The data provide evidence of the influence of seeded scaffolds on bone remodeling in the area of the defect.Materials and methods. The Local Ethics Committee of the North-Western State Medical University named after I.I. Mechnikov gave permission for the practical part of the research work. The study included 29 white laboratory mice. Molars were extracted and a bone defect was formed. Pulp and periodontal stem cells were obtained and cell-seeded scaffolds were made, then they were introduced into the defect area. The animals were euthanized, maxillofacial CT scan and histology of the defect area were performed 28 days after the molar extraction.Results. The oral cavity of mice was examined, molars were extracted, and teeth were morphologically examined under anesthesia. Scaffolds were synthesized and bone defects were filled. CT scans and histology results were analyzed. The bone volume increased in the main group compared to the control group.Conclusion. The fibrin glue can be used to obtain a material with mechanical characteristics sufficient for a stable shape scaffold. The study proved that the pulp stem cells enclosed in a fibrin glue-based scaffold can maintain the ability to proliferate and osteogenically differentiate. The scaffold based on fibrin glue, which we used, affected the bone remodeling process in the area of jaw defects.