비스무스옥사이드를 조영제로 사용하는 MTA는 변색의 가능성이 있으므로 심미성이 요구되는 부위는 사용하지 않는 것이 좋습니다!
국내 유통중인 비스무스옥사이드를 조영제로 사용하는 MTA들
OrthoMTA, Endocem gray, Prorrot MTA, MTA angelus
Dental discoloration caused by bismuth oxide in MTA in the presence of sodium hypochlorite.
- 1Department of Dentistry, Dental School of Bauru, University of São Paulo - USP, Bauru, SP, Brazil.
Abstract
OBJECTIVES:
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.
MATERIALS AND METHODS:
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.
RESULTS:
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.
CONCLUSIONS:
MTA Angelus in contact with a tooth previously immersed in sodium hypochlorite resulted in colour alteration at the cement/dentine interface.
CLINICAL RELEVANCE:
MTA Angelus should not be used after irrigation with sodium hypochlorite as this will result in tooth discoloration
