Van Den Vreken Natasja M F, Pieters Ilse Y, De Maeyer Erna A P, Jackers Geert J, Schacht Etienne H, Verbeeck Ronald M H
Department of Dental Materials Science, Ghent University, De Pintelaan 185 (P8), B-9000 Ghent, Belgium.
J Biomater Sci Polym Ed. 2006;17(9):953-67. doi: 10.1163/156856206778366040.
The objective of this study was to investigate the conversion of alpha-Ca3(PO4)2 (alpha-TCP) in composite bone cements based on a water-degradable polyester matrix as a function of the polymer formulation and the alpha-TCP filler content. Cross-linkable dimethacrylates of epsilon-caprolactone/ D,L-lactide co-polymer or of epsilon-caprolactone/glycolide co-polymer were mixed with hydroxyethylmethacrylate, a photo-initiator and alpha-TCP to obtain composites with a filler content of 80 or 40 wt% alpha-TCP. The disk shaped composite samples were set by visible light irradiation and immersed in HEPES at 37 degrees C. At selected times the samples were removed from the solution and analysed with X-ray diffractometry and infrared spectroscopy. Conversion of alpha-TCP into calcium-deficient hydroxyapatite (CDHAp) was observed for all composites, but the reaction was not completed after 8 weeks immersion. The conversion rate of alpha-TCP and the crystallinity of the formed apatite apparently were not affected by the type of polyester used, but significantly depended on the alpha-TCP content of the composites. An increase of the amount of alpha-TCP in the composite resulted in a slower formation of CDHAp with a higher crystallinity.
本研究的目的是研究基于水可降解聚酯基体的复合骨水泥中α - 磷酸三钙（α - TCP）的转化情况，该转化是聚合物配方和α - TCP填料含量的函数。将ε - 己内酯/D，L - 丙交酯共聚物或ε - 己内酯/乙交酯共聚物的可交联二甲基丙烯酸酯与甲基丙烯酸羟乙酯、光引发剂和α - TCP混合，以获得填料含量为80 wt%或40 wt%α - TCP的复合材料。将圆盘状复合样品通过可见光照射固化，并浸入37℃的HEPES中。在选定的时间从溶液中取出样品，并用X射线衍射和红外光谱进行分析。所有复合材料均观察到α - TCP向缺钙羟基磷灰石（CDHAp）的转化，但浸泡8周后反应未完成。α - TCP的转化率和所形成磷灰石的结晶度显然不受所用聚酯类型的影响，但显著取决于复合材料中α - TCP的含量。复合材料中α - TCP含量的增加导致CDHAp形成较慢且结晶度较高。
