PhD student, Centro de investigação interdisciplinar Egas Moniz (CiiEM), Instituto Universitário Egas Moniz, Caparica, Portugal; Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, University of Lisbon, Lisbon, Portugal.
Master student in Dental Medicine, Instituto Universitário Egas Moniz, Caparica, Portugal.
J Prosthet Dent. 2021 Apr;125(4):705.e1-705.e7. doi: 10.1016/j.prosdent.2021.01.002. Epub 2021 Feb 15.
Dental cements that release monomers that negatively impact adjacent oral soft tissues may adversely affect clinical outcomes. However, in vitro studies evaluating the cytotoxic and genotoxic potential of substances released from dental cements are lacking.
The purpose of this in vitro study was to define and compare the cytotoxicity and genotoxicity of the eluates of a self-adhesive resin cement (RelyX Unicem 2 Automix) autopolymerized and light polymerized with 2 other types of luting cements: a glass ionomer cement (Ketac Cem Easymix) and a resin-modified glass ionomer cement (Ketac Cem Plus).
The eluates were prepared, and 3T3 mouse fibroblast cells were exposed for 24 hours to serial eluate dilutions of the 3 types of cement. Cytotoxicity was determined by using a cell viability assessment through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and crystal violet assays. Genotoxic effects were determined by using the cytokinesis-block micronucleus assay.
Cell viability was higher in the presence of the glass ionomer cement eluate than of the resin-modified glass ionomer cement and resin cement eluates. A pronounced decrease in viability was found when the cells were exposed to undiluted samples of resin-modified glass ionomer cement (around 50%) or resin cement (around 80% to 90%). No significant difference in cell viability was found between autopolymerized and light-polymerized resin cements. All cements induced a dose-dependent response of mononucleated cell formation. However, only the resin cements showed double strand breaks significant differences in the deoxyribonucleic acid (DNA) molecules against the basal DNA lesions that occurred spontaneously.
The glass ionomer cement was not found to be cytotoxic or genotoxic, whereas the eluates derived from the resin-modified glass ionomer cement and resin cement, independently of the polymerization method, were cytotoxic in fibroblast cells. Maximum cytotoxicity was observed in the presence of resin cement, which also showed genotoxicity, independently of being light polymerized.
释放对邻近口腔软组织有负面影响的单体的牙科水门汀可能会对临床结果产生不利影响。然而，目前缺乏评估牙科水门汀释放物质的细胞毒性和遗传毒性的体外研究。
本体外研究的目的是定义和比较自粘树脂水门汀（RelyX Unicem 2 Automix）自聚和用 2 种其他类型的粘固水门汀（玻璃离子水门汀（Ketac Cem Easymix）和树脂改性玻璃离子水门汀（Ketac Cem Plus）光聚合后浸提液的细胞毒性和遗传毒性。
制备浸提液，将 3T3 小鼠成纤维细胞暴露于 3 种水门汀的系列浸提液稀释液中 24 小时。通过 3-（4,5-二甲基噻唑-2-基）-2,5-二苯基四氮唑溴化物（MTT）和结晶紫测定法评估细胞活力来确定细胞毒性。通过胞质分裂阻断微核试验确定遗传毒性效应。
玻璃离子水门汀浸提液存在时细胞活力高于树脂改性玻璃离子水门汀和树脂水门汀浸提液。当细胞暴露于未稀释的树脂改性玻璃离子水门汀（约 50%）或树脂水门汀（约 80%至 90%）时，发现细胞活力明显下降。自聚和光聚合树脂水门汀之间的细胞活力无显著差异。所有水门汀均诱导单核细胞形成剂量依赖性反应。然而，只有树脂水门汀显示出与自发发生的基础 DNA 损伤相比，脱氧核糖核酸（DNA）分子的双链断裂显著差异。
玻璃离子水门汀未显示出细胞毒性或遗传毒性，而树脂改性玻璃离子水门汀和树脂水门汀的浸提液，无论聚合方法如何，在成纤维细胞中均具有细胞毒性。在存在树脂水门汀的情况下观察到最大细胞毒性，该树脂水门汀也显示出遗传毒性，而无论是否进行光聚合。
