疾病动物模型,种植体周围骨缺损修复 z-bio 2021-03-16 298

　　Implant restoration is becoming more and more widespread in clinical practice, but it usually involves excessive absorption of alveolar bone after tooth loss due to trauma, tumor, periodontal disease, etc., resulting in insufficient bone mass and implanted dentures. Wangong et al. used small experimental pigs in China to combine bone marrow stromal stem cells with hydroxyapatite and tricalcium phosphate complex to form a biomaterial complex, which combined with the bone defect around the implant. Applied and analyzed the bone defect around the implant. Characteristics of tissue regeneration.

　　Experimental process: (1) Extraction of bone marrow mesenchymal stem cells and induction of differentiation culture: 5 to 7ml of bone marrow is aseptically extracted from the superior anterior superior spines of miniature pigs and placed in a heparinized centrifuge tube. After density gradient centrifugation, the cells were suspended in α-MEM medium containing 10% fetal bovine serum, inoculated into culture flasks and placed in a CO2 incubator. After 24 hours, the cells adhered to the wall, and 80% after fusion digestion. Passage and harvest the second-generation cells for later use. (2) Identification of BMSC: digest and count the purified BMSCs of the 7th generation culture. Add 100μl of cell suspension containing 1 x 106 cells to the centrifuge tube. Add 200μl PBS, centrifuge at 1000/min for 5 minutes, then add 200μl PBS to resuspend the cells, add FITC-labeled CD71, CD44, CD34, CD45 monoclonal antibodies, react for 1 hour in the dark at room temperature, and then fix with paraformaldehyde. Detected by flow cytometry. (3) Combined culture of cells and scaffold materials: adjust the cell concentration to 1 x 106/100μl, place them in a medium containing hydroxyapatite-tricalcium phosphate carrier material, shake gently, and culture under standard conditions 7 I days. (4) Bone defect and repair around the implant: A cylindrical bone defect with a diameter of 3 mm and a height of 5 mm was formed on the middle wall of the implant bed. The BMSC-HA/TCP composite and HA-TCP material (80% tricalcium phosphate and 20% hydroxyapatite) were transplanted into each group, covered with Cellfoam membrane and tightly sutured. Eight miniature pigs were randomly divided into cell scaffold group and scaffold group, 4 pigs in each group were sacrificed, and 2 pigs were sacrificed 1 month and 3 months after transplantation. The materials were collected separately, bone mill sections were made, stained with toluidine blue, and histological observations were performed. Experimental results: One month after transplantation of the cell scaffold group, new bone formation was observed in the middle bone defect, the toluidine blue stained bright blue, the osteoblasts and woven bone lined up neatly, and active growth was observed. Skeletal activity. In the 3-month group, good osseointegration was mainly formed in dense bone, and it can be seen that the bone was mainly composed of mature dense bone, including many Haval systems. It can be seen that most of the scaffolding material is broken down and replaced by new bones, blood vessels grow into the gaps of the material, and there is no obvious inflammatory response. There are trabecular bone formation and the structure of the Haval system. One month after transplantation into the stent group, there was a clear gap between the stent material and the implant at the bone defect. Three months later, the stent material gradually deteriorated and no new bone formation was seen.