Marciano Marina Angélica, Duarte Marco Antonio Hungaro, Camilleri Josette
Department of Dentistry, Dental School of Bauru, University of São Paulo - USP, Bauru, SP, Brazil.
Department of Restorative Dentistry, Faculty of Dental Surgery, Medical School, University of Malta, Msida, MSD 2090, Malta.
Clin Oral Investig. 2015 Dec;19(9):2201-9. doi: 10.1007/s00784-015-1466-8. Epub 2015 Apr 30.
The aim of this research was to analyse the dental discolouration caused by mineral trioxide aggregate (MTA) induced by bismuth oxide and also assess the colour stability of other dental cements.
Bismuth oxide, calcium tungstate and zirconium oxide were placed in contact with sodium hypochlorite for 24 h after which they were dried and photographed. Phase analyses were performed by X-ray diffraction (XRD) of radiopacifiers before and after immersion in sodium hypochlorite. Furthermore, teeth previously immersed in water or sodium hypochlorite were filled with MTA Angelus, Portland cement (PC), PC with 20 % zirconium oxide, PC with 20 % calcium tungstate and Biodentine. Teeth were immersed for 28 days in Hank's balanced salt solution after which they were sectioned and characterized using scanning electron microscopy (SEM) with energy-dispersive mapping and stereomicroscopy.
Bismuth oxide in contact with sodium hypochlorite exhibited a change in colour from light yellow to dark brown. XRD analysis demonstrated peaks for radiopacifier and sodium chloride in samples immersed in sodium hypochlorite. The SEM images of the dentine to material interface showed alteration in material microstructure for MTA Angelus and Biodentine with depletion in calcium content in the material. The energy-dispersive maps showed migration of radiopacifier and silicon in dentine.
MTA Angelus in contact with a tooth previously immersed in sodium hypochlorite resulted in colour alteration at the cement/dentine interface.
MTA Angelus should not be used after irrigation with sodium hypochlorite as this will result in tooth discoloration.
本研究旨在分析由氧化铋诱导的矿物三氧化物凝聚体（MTA）引起的牙齿变色情况，并评估其他牙科水门汀的颜色稳定性。
将氧化铋、钨酸钙和氧化锆与次氯酸钠接触24小时，之后将它们干燥并拍照。通过对浸入次氯酸钠前后的射线阻射剂进行X射线衍射（XRD）分析来进行相分析。此外，将先前浸入水或次氯酸钠中的牙齿用MTA Angelus、波特兰水泥（PC）、含20%氧化锆的PC、含20%钨酸钙的PC和生物活性齿科修复材料进行充填。将牙齿浸入汉克斯平衡盐溶液中28天，之后将其切片，并使用带有能谱分析的扫描电子显微镜（SEM）和体视显微镜进行表征。
与次氯酸钠接触的氧化铋颜色从浅黄色变为深棕色。XRD分析表明，浸入次氯酸钠的样品中存在射线阻射剂和氯化钠的峰。牙本质与材料界面的SEM图像显示，MTA Angelus和生物活性齿科修复材料的材料微观结构发生改变，材料中的钙含量减少。能谱图显示射线阻射剂和硅在牙本质中的迁移。
MTA Angelus与先前浸入次氯酸钠的牙齿接触会导致水门汀/牙本质界面出现颜色改变。
用次氯酸钠冲洗后不应使用MTA Angelus，因为这会导致牙齿变色。
