Interdepartment Research Group for the Applied Scientific Collaboration (IRGASC), Division of Biomaterials & Bioengineering, Technical University of Catalonia (UPC), Avda. Diagonal 647, 08028, Barcelona, Spain.
J Mater Sci Mater Med. 2012 Sep;23(9):2081-90. doi: 10.1007/s10856-012-4686-3. Epub 2012 May 26.
α-Tricalcium phosphate (α-TCP) has become the main reactant of most experimental and commercial ceramic bone cements. It has calcium-to-phosphorus (Ca/P) ratio of 1.50. The present study expands and reports on the microstructures and mechanical properties of calcium phosphate (CP) cements containing sintered monolithic reactants obtained in the interval 1.29 < Ca/P < 1.77. The study focuses on their cement setting and hardening properties as well as on their microstructure and crystal phase evolution. The results showed that: (a) CP-cements made with reactants with Ca/P ratio other than 1.50 have longer setting and lower hardening properties; (b) CP-cements reactivity was clearly affected by the Ca/P ratio of the starting reactant; (c) reactants with Ca/P < 1.50 were composed of several phases, calcium pyrophosphate and α- and β-TCP. Similarly, reactants with Ca/P > 1.50 were composed of α-TCP, tetracalcium phosphate and hydroxyapatite; (d) only the reactant with Ca/P = 1.50 was monophasic and was made of α-TCP, which transformed during the setting into calcium deficient hydroxyapatite; (e) CP-cements developed different crystal microstructures with specific features depending on the Ca/P ratio of the starting reactant.
α-磷酸三钙（α-TCP）已成为大多数实验和商业陶瓷骨水泥的主要反应物。它的钙磷（Ca/P）比为 1.50。本研究扩展并报告了钙磷（CP）水泥的微观结构和力学性能，其中包含在 1.29 < Ca/P < 1.77 范围内获得的烧结整体反应物。研究重点是它们的水泥凝固和硬化特性以及它们的微观结构和晶体相演变。结果表明：（a）CP 水泥的凝固和硬化性能随着反应物 Ca/P 比的增加而延长和降低；（b）CP 水泥的反应性明显受起始反应物 Ca/P 比的影响；（c）Ca/P < 1.50 的反应物由焦磷酸钙和 α-和 β-TCP 组成。同样，Ca/P > 1.50 的反应物由 α-TCP、磷酸四钙和羟基磷灰石组成；（d）只有 Ca/P = 1.50 的反应物是单相的，由 α-TCP 组成，在凝固过程中转化为缺钙羟基磷灰石；（e）CP 水泥根据起始反应物的 Ca/P 比发展出具有特定特征的不同晶体微观结构。
