Dual setting mineral cements with polymerisable organic matrix based on degradable polymers

由于陶瓷水泥基质的脆性，无机生物水泥应用于承重缺陷的扩展受到限制。该项目涉及无机-有机复合材料，该材料由矿物水泥相和溶解在水泥液中的原位交联聚合物相组成。这样的双固化糊剂应提供高的抗压强度和足够的抗内聚性，直到无机水泥固化，以及由于聚合物含量而改善的弯曲强度和断裂功。一般目的是合成无机相和聚合物相的可降解基质，使得通过天然骨组织的替代获得完全的材料再吸收。无机水泥相在酸性或中性条件下凝固以形成可降解的水合磷酸钙和磷酸镁，例如透钙磷石（CaHPO 4 * 2 H2O）或鸟粪石（MgNH 4PO 4 * 6 H2O）。对有机基质的要求是多功能、水溶性单体和预聚物，这些单体和预聚物衍生自聚乙二醇或聚甘油，具有甲基丙烯酸酯（交联）、酯（例如，丙交酯、降解）和磷酸盐部分（骨水泥粘附）。将在与成骨细胞接触的情况下测试材料的细胞相容性，同时通过在材料表面培养成骨细胞来证明降解行为。生物力学性能进行了分析，通过使用静态和动态测试制度。

An extension of the application of inorganic biocements to load-bearing defects is limited due to the brittle nature of the ceramic cement matrices. The proposed project deals with inorganic-organic composite materials which consist of a mineral cement phase and an in situ cross-linkable polymer phase which is dissolved in the cement liquid. Such dual-setting pastes should provide both a high compressive strength and a sufficient cohesion resistance until inorganic cement setting as well as an improved bending strength and work of fracture due to the polymer content. A general aim is the synthesis of degradable matrices of both the inorganic and the polymer phase such that a full material resorption is obtained with the replacement by native bone tissue. The inorganic cement phase set under acidic or neutral conditions to form degradable, hydrated calcium and magnesium phosphates such as brushite (CaHPO4*2H2O) or struvite (MgNH4PO4*6H2O). Requirements for the organic matrix are multifunctional, water soluble monomers and prepolymers derived from polyethylenglycol or polyglycidols with methacrylic (cross-linking), ester (e.g. lactide, degradation) and phosphate moieties (cement adhesion). The materials will be tested in contact to osteoblasts regarding their cytocompatibility while the degradation behaviour is demonstrated by cultivation of osteoclastic cells on the materials surface. The biomechanical performance is analysed by using both static and dynamic testing regimes.