纯锌引导性骨再生屏障膜的降解调控及其促成骨机制

Guided bone regeneration (GBR) membrane plays an important role in guided bone regeneration technology, and is a research hot topics in the field of dental materials. At present, the widely used collagen membrane in clinic has the problems of insufficient mechanical properties and degrades rapidly. Titanium membrane and PTFE membrane have the risk of poor plasticity, wound dehiscence and membrane exposure, which can not be degraded and need to be removed by second operation. Magnesium alloy membrane degrades too fast and has poor plasticity. The applicant proposed the original idea of using pure zinc with good plasticity as GBR membrane. Pure zinc is superior to collagen in mechanical properties，and its degradation products zinc ions can promote bone formation, which is expected to be an ideal membrane material for GBR. This project intends to design pure zinc GBR membranes with different thickness and pore size. The mechanical properties, degradation performance, biocompatibility, adhesion ability, proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells will be studied through systematic in vivo and in vitro experiments. Secondly, the degradation of pure zinc GBR membranes on bone remodeling will be studied through animal experiments using Bio-Gide collagen membrane and titanium membrane as control. Thirdly, to elucidate the whole-cycle degradation mechanism of pure zinc and the mechanism of bone formation.

引导性骨再生（GBR）屏障膜在引导骨再生技术中发挥了重要作用，是口腔材料领域的研究热点之一。目前临床上应用的胶原膜存在力学性能不足、降解过快的问题；钛膜与聚四氟乙烯膜存在可塑性差、伤口裂开与膜暴露的风险，无法降解，需二次手术的取出；镁合金膜降解过快且可塑性差。申请人提出利用可塑性好的纯锌做为GBR屏障膜的原创性想法。纯锌的力学性能优于胶原，在体内降解产生的锌离子能够促进骨形成，有望成为理想的GBR屏障膜材料。本项目拟设计不同厚度与孔径的纯锌GBR屏障膜，通过系统的体内外实验，①研究其力学性能、降解性能、生物相容性及对骨髓间充质干细胞黏附、增殖与成骨向分化的能力；②采用Bio-Gide胶原膜、钛膜作对照，通过动物植入实验研究纯锌GBR屏障膜的降解对骨组织重建的影响规律；③阐明纯锌全降解周期的降解机理及促成骨机制。

研发新型引导性骨再生（GBR）膜是口腔材料领域的研究热点。本研究以厚度30μm的轧制态纯锌膜为原材料，通过激光打孔制备出300μm孔径和1000μm孔径的纯锌膜。无孔锌膜的力学性能良好，激光打孔降低了膜材料的延伸率。无孔锌膜和300μm孔径锌膜的降解速率相对适宜，在Hanks’溶液中浸泡60天或在植入大鼠颅骨10周后仍能保持相对完整。而1000μm孔径锌膜因降解速率较快，而过早地失去了力学完整性，在体内植入6周时已部分塌陷至骨缺损区域，影响了后期的骨再生。三种纯锌膜均表现出良好的生物相容性，其中300μm孔径纯锌膜的促成骨能力最强，表明纯锌膜在新型可降解GBR膜领域具有一定潜力。