Functionalisation of periodic cellular bioactive glass scaffolds via the tailored design of compositional gradients

三维，高多孔性和细胞生物活性的玻璃支架对于原位（通过直接植入患者体内）或非原位（通过组织工程）的组织再生都很感兴趣。由于生物活性玻璃明显的结晶倾向，抑制了密集支架支柱的烧结，这些结构通常具有较差的机械稳定性，例如抗压强度低于1mpa。这使得机械加固是必要的，这通常是通过与聚合物结合来实现的。这里提出了一种双重方法，通过使用不同的玻璃类型（例如硅酸盐和磷酸盐），将新的支架几何形状与无机功能化相结合，以获得成分梯度。分析了玻璃层烧结过程中扩散过程的影响，探讨了这种梯度的形成。此外，梯度对降解和离子释放的影响以及对支架机械稳定性的影响将被表征。新的支架几何形状将通过立体光刻技术对聚合物模板进行增材制造，然后通过复制方法进行支架合成。除了将CAD模型与支架显微计算机断层扫描进行直接比较以研究模板精度外，对真实结构模型进行有限元模拟将有助于了解支架的力学行为。

Three-dimensional, highly porous and cellular bioactive glass scaffolds are of interest for tissue regeneration both in situ (by direct implantation into the patient) or ex situ (via tissue engineering). Owing to the pronounced crystallisation tendency of bioactive glasses, which inhibits the sintering of dense scaffold struts, these constructs often suffer from poor mechanical stability, e.g. compressive strengths below 1 MPa. This makes mechanical reinforcement necessary, which typically is achieved by combination with polymers. Here, a two-fold approach is addressed, which combines new scaffold geometries with inorganic functionalisation by the use of different glass types (e.g. silicate and phosphate) to obtain compositional gradients. The influence of diffusion processes during the sintering of glass layers is analysed to investigate the formation of such gradients. In addition, the influence of gradients on both degradation and ion release but also on scaffold mechanical stability will be characterised. New scaffold geometries will be obtained by additive manufacturing ofpolymer templates via stereo lithography, followed by scaffold synthesis via the replica approach. Besides the direct comparison of CAD models with scaffold micro-computer tomography scans to investigate templating precision, FEM simulations on real structuremodels will help to understand scaffold mechanical behaviour.