[Evaluation of the effect of 3D printed HAP-GEL scaffold combined with BMSCs and HUVECs in repairing rabbit skull defect].

PURPOSE: To qualitatively analyze the effect of 3D printed hydroxyapatite-gel (HAP-GEL) scaffold combined with bone marrow mesenchymal stem cells (BMSCs) and human umbilical vein endothelial cells (HUVECs) in repairing rabbit skull defect. METHODS: The third generation BMSCs and HUVECs were co-cultured with 3D printed HAP-GEL scaffold to construct tissue engineering bone. The rabbit model of skull defect was established and randomly divided into 4 groups. HAP-GEL stent, HAP-GEL stent + BMSCs and HUVECs cells were implanted respectively, and positive control (autologous bone tissue) and blank control were set up. Twelve weeks after operation, X-ray, cone-beam CT (CBCT) scan and H-E staining were performed to observe and analyze the changes of bone defect qualitatively. RESULTS：Twelve weeks after operation, imaging examination (X-ray and CBCT) showed that there was still obvious circular transmission in the blank control group, and the density was increased and the defect boundary was blurred in both HAP-GEL stent combined cell group and HAP-GEL group, among which the bone was continuous and the bone mineral density was the highest in HAP-GEL stent composite cell group, which was close to normal tissue. The results of H-E staining at twelve weeks showed that compared with the blank control group and the HAP-GEL group, the defect area of the HAP-GEL composite group was filled with new bone and bone-like tissue, the scaffold material was degraded and there was new bone formation inside the scaffold, and the bone repair effect was good, and the osteogenic effect was similar to that of the positive control group. CONCLUSIONS: 3D printed HAP-GEL scaffold + BMSCs + HUVECs cell complex has good osteogenic ability and biocompatibility with a good effect on repairing rabbit skull defect.

[Experiment study on the repair of rabbit skull defect with HAP-GEL scaffolds combined with cultured osteoblast].

PURPOSE: To investigate the ability of composite graft of osteoblasts and HAP-GEL scaffolds to repair cranial bone defect. METHODS: HAP-GEL and osteoblasts were co-cultured. The rabbit cranial parietal bone defect models were established. HAP-GEL scaffolds and osteoblasts were implanted into the cranial bone defect with blank defect as negative control, autologous skull as positive control. After 4,8,12 weeks, the result was evaluated by gross inspection, three-dimensional computed tomographic scanning and histological examination, respectively. RESULTS: After 4, 8, 12 weeks, blank defects displayed significantly radiolucent area, HAP-GEL with osteoblasts and autologous skull restoration showed high density area, the edges were slightly blur. With time going by, part of the scaffolds were absorbed, and the new bone trabecular was observed in histological examination. In the control groups, only fibrous tissues were observed in the defect region, there was no new bone formation. CONCLUSIONS: the engineering bone constructed by osteoblasts and HAP-GEL scaffold can be applied to repair bone defect.