Expansion Technique With PVA For Oral Sofe Tissue:an Experimemtal Study

[objective] The purpose of this article is to study the feasibility of polyvinyl alcohol hydrogel expansion the oral mucoperiostal in animal models by applying polyvinyl alcohol hydrogel water swelling principle. In order to provide a new fixation for the oral soft tissue defects.[Methods] Application of the polymer solution or sol dispersed particles interconnected in some parts of the space grid structure is formed, and the dispersion medium full grid structure gap, into a semi-solid material technology combined with constant temperature water bath oscillator box oven temperature to prepare a polymer concentration of25%polyvinyl alcohol hydrogel. Volume are14mm*2mm*3mm, weight0.15g PVA hydrogel,4groups of20male rabbits were implanted into the maxillary alveolar bone periosteum after implantation,and another4male rabbits as blank control. the animals were sacrificed after one, two, three, four week. TS-12J biological tissue microcomputer dehydrator, BM-Ⅸ biological tissue embedding machine, refrigeration units, RM2235slicer, CS-Ⅳ type eject baking machine production expansion area mucoperiostal and bone tissue sections using Olympus Sri Lanka CX40microscope and Nikon cameras histomorphometry observation and histological observation and recording the length of tissue and mucoperiosteum cross-sectional, the hyperplasia in Collagen fiber and the count of blood vessels, the osteoclast number and bone lacunae.[Results](1) Electron microscopy concentration of25%polyvinyl alcohol hydrogel uneven surface morphology after drying, and was a regular cord-like projections, the gel network structure compact paste, and then swollen with a polyethylene concentration of15%alcohol hydrogel relatively dense mesh, mesh small.(2) Visual observation with the increase of the polyvinyl alcohol hydrogel implant time, polyvinyl alcohol hydrogel volume gradually increased, the implanted area mucoperiostal gradually uplift, good wound closure, no abnormal the mucoperiosteal color morphology and normal tissue.(3) With the increase of the polyvinyl alcohol hydrogel implant time, the the implanted zone sticky periostitis cell number gradually reduced to achieve the highest value for the first week after implantation of inflammatory cells, expansion zone in the fourth week sticky periostitis the amount of inflammatory cells in the tissue of cell volume control is basically the same.(4) Using a microscope to observe and measure, with the increase of the polyvinyl alcohol hydrogel implant time the expansion area mucoperiostal cell layers length increases, the length of the cell layers in the fourth week increase to about expansion1.8times the length of the cell.(5) The expansion zone of periosteum within the amount of collagen fibers is a growing trend with increasing expansion is detected when the fourth week of collagen fibers is about5times the pre-expansion of the amount of collagen fibers.(6) Expansion the area sticking periosteum number of blood vessels peaked in the third week, the fourth week with the expansion area mucoperiostal the complete healing the mucoperiosteal number of blood vessels in the number of blood vessels and the expansion of basic equal.(7) As the polyvinyl alcohol to expansion the mucoperiosteal the time increase, the number of osteoclasts and bone lacunae of bone tissue of the expansion zone presents the increasing trend after expansion for four weeks.[Conclusion](1)SPA gels expansion technique is able to form extra palatine mucoperiosteal tissue,which could be a new restoration approach to sofe tissue defect and others.(2) After PVA hydrogel implants in rabbits maxillary mucoperiosteal within a certain time to make observations from histomorphometry uplift of mucoperiosteum.(3) PVA hydrogel absorbent after the expansion mucoperiosteal from histology with the expansion of Performance.(4) PVA hydrogel expansion within a certain time does not cause the absorption of bone tissue expansion area by rabbit animal experiments carried out using the superabsorbent oral soft tissue expansion is feasible for clinical oral soft tissue defects lay a good foundation.