Hsieh Sung-Chih, Teng Nai-Chia, Lin Yu-Chen, Lee Pei-Ying, Ji Dian-Yu, Chen Chien-Chung, Ke En-Sheng, Lee Sheng-Yang, Yang Jen-Chang
School of Dentistry, Taipei Medical University, Taipei, Taiwan, ROC.
J Endod. 2009 Sep;35(9):1292-5. doi: 10.1016/j.joen.2009.06.007. Epub 2009 Jul 22.
Mineral trioxide aggregate (MTA) fulfills many of the ideal properties of a root end filling material and repair material for furcal perforation. However, its low cohesive property often makes it difficult to handle. To improve the handling properties of MTA root canal filling materials, MTA-like cement was made, and calcium lactate gluconate (CLG) aqueous solution was used to shorten the setting time and enhance the paste viscosity.
CLG solution was prepared by mixing lactic acid, glucono delta lactone, and calcium oxide by wet process. The crystalline property of the CLG powder was characterized by x-ray diffraction. The MTA-like cements were prepared by mixing Portland cement/bismuth oxide/gypsum (75/20/5); ProRoot white MTA (Dentsply Tulsa Dental, Tulsa, OK) was used as a control group. The influence of various liquid phases on initial setting time, handling properties, and pH value were investigated by a Vicat needle, questionnaire of operational hand feel, and pH meter, respectively.
By using 23.1 wt% CLG solutions as a liquid phase, the setting time of white MTA was significantly decreased from 155.5 +/- 5.0 to 12.3 +/- 2.5 minutes. The pH values for hydrated white MTA with deionized water and 23.1 wt% CLG solutions were 12.29 +/- 0.02 and 11.81 +/- 0.04 at 72 hours.
The results suggest that the addition of amorphous CLG-based liquid phase provides improvement in sealing ability as well as clinical manageability of dental filling materials.
三氧化矿物凝聚体（MTA）具备许多作为根尖充填材料和髓室底穿孔修补材料的理想特性。然而，其较低的内聚性常常使其难以操作。为改善MTA根管充填材料的操作性能，制备了类MTA水泥，并使用葡萄糖酸钙乳酸盐（CLG）水溶液来缩短凝固时间并提高糊剂粘度。
通过湿法混合乳酸、葡萄糖酸δ内酯和氧化钙制备CLG溶液。用X射线衍射对CLG粉末的晶体特性进行表征。通过混合波特兰水泥/氧化铋/石膏（75/20/5）制备类MTA水泥；使用ProRoot白色MTA（登士柏塔尔萨牙科公司，塔尔萨，俄克拉何马州）作为对照组。分别通过维卡针、操作手感问卷和pH计研究不同液相成分对初凝时间、操作性能和pH值的影响。
使用23.1 wt%的CLG溶液作为液相时，白色MTA的凝固时间从155.5±5.0分钟显著缩短至12.3±2.5分钟。72小时时，用去离子水和23.1 wt%的CLG溶液水合的白色MTA的pH值分别为12.29±0.02和11.81±0.04。
结果表明，添加基于无定形CLG的液相可提高牙科充填材料的密封能力以及临床可操作性。
