KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & UZ Leuven (University Hospitals Leuven), Dentistry, Kapucijnenvoer 7, 3000 Leuven, Belgium.
Department of Public Health and Primary Care, Centre for Environment and Health, KU Leuven (University of Leuven), Kapucijnenvoer 35/5, 3000 Leuven, Belgium.
Dent Mater. 2020 Feb;36(2):270-283. doi: 10.1016/j.dental.2019.11.009. Epub 2019 Dec 15.
To determine the cytotoxic and genotoxic potential of the respirable fraction of composite dust (<4 μm) on human bronchial epithelial cells.
Composite sticks of three commercial dental composites (Filtek Supreme XTE, Grandio, Transbond XT) were ground in an enclosed plexiglass chamber with a rough dental bur (grain-size 100 μm) and the generated airborne respirable dust was collected in a personal cyclone on a teflon filter (pore size 5 μm). Immediately after particle collection, the dust was quantified gravimetrically and the particles were suspended in cell culturing medium. Next, human bronchial epithelial cells (16HBE14o-) were exposed to the suspensions (3 μg/ml-400 μg/ml). After 24 h, cell viability (WST-1 assay) and membrane integrity (LDH assay) were evaluated. Furthermore, the genotoxic effect of a sub-cytotoxic concentration (50 μg/ml) of composite dust was evaluated by the comet assay after 3 h exposure and cell cycle disturbances were analyzed by flow cytometry. Cellular uptake of particles was evaluated by transmission electronic microscope (TEM).
For all three tested composite materials, a decrease in metabolic activity of 10-35% was observed when the cells were exposed to the highest concentrations (100 μg/ml-400 μg/ml). Toxicity was partially linked to membrane disruption especially after 72 h exposure. All tested composites provoked a mild genotoxic effect after short-term exposure compared to the control groups. TEM revealed that respirable particles of all tested composites were taken up by the cells.
The respirable fraction of composite dust only showed cytotoxic effects at the highest concentrations, whereas mild genotoxicity was observed after exposure to a sub-cytotoxic concentration.
确定复合粉尘（<4 μm）可呼吸部分对人支气管上皮细胞的细胞毒性和遗传毒性。
将三种商用牙科复合材料（Filtek Supreme XTE、Grandio、Transbond XT）的复合棒在封闭的有机玻璃室中用粗糙的牙科钻头（粒度 100 μm）研磨，并将产生的可吸入呼吸性粉尘收集在聚四氟乙烯过滤器上的个人旋风器（孔径 5 μm）中。在收集颗粒后立即进行重量分析以量化粉尘，并将颗粒悬浮在细胞培养介质中。然后，将人支气管上皮细胞（16HBE14o-）暴露于悬浮液（3 μg/ml-400 μg/ml）中。24 小时后，通过 WST-1 测定法评估细胞活力，通过 LDH 测定法评估细胞膜完整性。此外，通过彗星试验评估亚细胞毒性浓度（50 μg/ml）复合粉尘暴露 3 小时后的遗传毒性效应，并通过流式细胞术分析细胞周期紊乱。通过透射电子显微镜（TEM）评估颗粒的细胞内摄取。
对于所有三种测试的复合材料，当细胞暴露于最高浓度（100 μg/ml-400 μg/ml）时，代谢活性下降 10-35%。毒性部分与膜破坏有关，特别是在暴露 72 小时后。与对照组相比，所有测试的复合材料在短期暴露后均引起轻度遗传毒性效应。TEM 显示所有测试的复合材料的可呼吸颗粒均被细胞摄取。
复合粉尘的可呼吸部分仅在最高浓度时显示出细胞毒性作用，而在暴露于亚细胞毒性浓度时观察到轻度遗传毒性。
