Tancred D C, McCormack B A, Carr A J
Bioengineering Research Centre, Department of Mechanical Engineering, University College Dublin, Ireland.
Biomaterials. 1998 Oct;19(19):1735-43. doi: 10.1016/s0142-9612(98)00082-9.
Previous work has shown that small additions of a phosphate glass (CaO-P2O5) can significantly enhance the sinterability and strength of hydroxyapatite. However, there are no quantitative phase analyses available for these materials which would provide indicators of biocompatibility and resorbability. Similarly, there is little information available about the mechanical properties, especially with high glass additions. In this study, the effects of sintering hydroxyapatite with phosphate glass additions of 2.5, 5, 10, 25, and 50 wt.% are quantified. Each composition was sintered over a range of temperatures, and quantitative phase analysis was carried out using XRD. In addition, the microstructures were studied using RLOM and SEM, and mechanical properties (Vickers hardness, KIC, and MOR) measured. These results may be used to indicate which compositions and processing conditions may provide materials suitable for use in hard tissue replacement. Composites containing up to 10 wt.% glass additions formed dense HA/TCP composite materials possessing flexural strength and fracture toughness values up to 200% those of pure HA. The HA/TCP ratio was strongly dependent on the percentage glass addition. Higher glass additions resulted in composites containing beta-TCP together with large amounts of alpha- or beta-calcium pyrophosphate, and having similar mechanical strengths to pure HA.
先前的研究表明，少量添加磷酸盐玻璃（CaO-P2O5）可显著提高羟基磷灰石的烧结性和强度。然而，目前尚无针对这些材料的定量相分析，而这种分析能提供生物相容性和可吸收性的指标。同样，关于其机械性能的信息也很少，尤其是高玻璃添加量时的情况。在本研究中，对添加2.5、5、10、25和50 wt.%磷酸盐玻璃的羟基磷灰石烧结效果进行了量化。每种成分在一系列温度下进行烧结，并使用XRD进行定量相分析。此外，利用反射光光学显微镜（RLOM）和扫描电子显微镜（SEM）研究了微观结构，并测量了机械性能（维氏硬度、断裂韧性KIC和抗弯强度MOR）。这些结果可用于表明哪些成分和加工条件能提供适用于硬组织替代的材料。添加量高达10 wt.%玻璃的复合材料形成了致密的HA/TCP复合材料，其抗弯强度和断裂韧性值比纯HA高出200%。HA/TCP比例强烈依赖于玻璃添加百分比。更高的玻璃添加量导致复合材料中含有β-TCP以及大量的α-或β-焦磷酸钙，并且其机械强度与纯HA相似。
