Camilleri J
Department of Building and Civil Engineering, University of Malta, Malta.
Int Endod J. 2008 Sep;41(9):791-9. doi: 10.1111/j.1365-2591.2008.01439.x.
To evaluate the chemical activity of Portland cement and two other cement types with similar chemical composition to mineral trioxide aggregate with the aim of developing these cements for further applications in dentistry.
The chemical composition of the three cement types namely Portland cement, calcium sulpho-aluminate cement and calcium fluoro-aluminate cement was evaluated by elemental analysis using energy dispersive analysis with X-ray under the scanning electron microscope and by X-ray diffraction analysis (XRD) to determine the phases. The constituents of the hydration reaction by-products were evaluated by XRD analysis of the set cements at 1, 7, 28 and 56 days and by analysis of the leachate by ion chromatography. The pH of both cements and leachate was determined at different time intervals. Cements admixed with micro-silica were also tested to determine the effect of micro-silica on the reaction by-products.
All three cement types were composed of tricalcium silicate as the main constituent phase. The hydration reaction of Portland cement produced calcium hydroxide. However, this was not present in the other cements tested at all ages. Admixed micro-silica had little or no effect on the cements with regard to reaction by-products. The pH of all cements tested was alkaline.
Both the experimental calcium sulpho-aluminate cement and calcium fluoro-aluminate cement had different hydration reactions to that of Portland cement even though calcium silicate was the major constituent element of both cement types. No calcium hydroxide was produced as a by-product to cement hydration. Micro-silica addition to the cement had no effect on the hydration reaction.
评估波特兰水泥以及另外两种化学成分与三氧化物矿物聚合体相似的水泥的化学活性，以便开发这些水泥在牙科领域的进一步应用。
通过扫描电子显微镜下的能量色散X射线分析进行元素分析以及通过X射线衍射分析（XRD）来确定相，从而评估三种水泥类型，即波特兰水泥、硫铝酸钙水泥和氟铝酸钙水泥的化学成分。通过对1、7、28和56天龄期的硬化水泥进行XRD分析以及通过离子色谱法分析渗滤液来评估水化反应副产物的成分。在不同时间间隔测定水泥和渗滤液的pH值。还测试了掺入微硅粉的水泥，以确定微硅粉对反应副产物的影响。
所有三种水泥类型均以硅酸三钙作为主要组成相。波特兰水泥的水化反应产生氢氧化钙。然而，在所有龄期测试的其他水泥中均未发现氢氧化钙。就反应副产物而言，掺入微硅粉对水泥几乎没有影响。所有测试水泥的pH值均呈碱性。
尽管硅酸钙是两种水泥类型的主要组成元素，但实验性硫铝酸钙水泥和氟铝酸钙水泥的水化反应与波特兰水泥不同。水泥水化没有产生氢氧化钙作为副产物。向水泥中添加微硅粉对水化反应没有影响。
