Department of Dentistry, Dental School of Bauru, University of São Paulo - USP, Bauru, SP, Brazil.
Department of Dentistry, Dental School of Bauru, University of São Paulo - USP, Bauru, SP, Brazil.
Dent Mater. 2016 Feb;32(2):e30-40. doi: 10.1016/j.dental.2015.11.008. Epub 2015 Dec 22.
Investigation of hydration, chemical, physical properties and porosity of experimental calcium silicate-based sealers.
Experimental calcium silicate-based sealers with calcium tungstate and zirconium oxide radio-opacifiers were prepared by mixing 1g of powder to 0.3 mL of 80% distilled water and 20% propylene glycol. MTA and MTA Fillapex were used as controls. The raw materials and set sealers were characterized using a combination of scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction. Physical properties were analyzed according to ANSI/ADA. The pH and calcium ion release were assessed after 3, 24, 72 and 168 h. The porosity was assessed using mercury intrusion porosimetry.
The analysis of hydration of prototype sealers revealed calcium hydroxide as a by-product resulting in alkaline pH and detection of calcium ion release, with high values in initial periods. The radiopacity was similar to MTA for the sealers containing high amounts of radio-opacifiers (p>0.05). Flowability was higher and film thickness was lower for resinous MTA Fillapex sealer (p<0.05). The test sealers showed water sorption and porosity similar to MTA (p>0.05).
The prototype sealers presented adequate hydration, elevated pH and calcium ion release. Regarding physical properties, elevated proportions of radio-opacifiers were necessary to accomplish adequate radiopacity, enhance flowability and reduce film thickness. All the tested sealers presented water sorption and porosity similar to MTA.
研究实验性硅酸钙基封固剂的水合作用、化学、物理性能和孔隙率。
通过将 1g 粉末与 0.3ml80%蒸馏水和 20%丙二醇混合，制备含有钨酸钙和氧化锆X 射线不透射性剂的实验性硅酸钙基封固剂。MTA 和 MTA Fillapex 用作对照。使用扫描电子显微镜、能量色散光谱和 X 射线衍射对原材料和凝固封固剂进行了特性描述。根据 ANSI/ADA 分析了物理性能。在 3、24、72 和 168 h 后，评估了 pH 值和钙离子释放。采用汞压入孔隙率法评估了孔隙率。
原型封固剂水合作用的分析表明，生成了副产品氢氧化钙，导致碱性 pH 值和钙离子释放的检测，在初始阶段具有较高的值。对于含有高浓度不透射性剂的封固剂，其放射不透性与 MTA 相似（p>0.05）。树脂状 MTA Fillapex 封固剂的流动性较高，薄膜厚度较低（p<0.05）。测试封固剂的吸水率和孔隙率与 MTA 相似（p>0.05）。
原型封固剂具有适当的水合作用、升高的 pH 值和钙离子释放。就物理性能而言，需要增加不透射性剂的比例以实现适当的放射不透性、增强流动性和降低薄膜厚度。所有测试的封固剂的吸水率和孔隙率与 MTA 相似。
