Salehi Satin, Gwinner Fernanda, Mitchell John C, Pfeifer Carmem, Ferracane Jack L
Division of Biomaterials and Biomechanics, Department of Restorative, School of Dentistry, Oregon Health Science University, Portland, OR, USA.
Division of Biomaterials and Biomechanics, Department of Restorative, School of Dentistry, Oregon Health Science University, Portland, OR, USA.
Dent Mater. 2015 Feb;31(2):195-203. doi: 10.1016/j.dental.2014.12.004. Epub 2015 Jan 3.
To determine the in vitro cytotoxicity of dental composites containing bioactive glass fillers.
Dental composites (50:50 Bis-GMA/TEGDMA resin: 72.5wt% filler, 67.5%Sr-glass and 5% OX50) containing different concentrations (0, 5, 10 and 15wt%) of two sol-gel bioactive glasses, BAG65 (65mole% SiO2, 31mole% CaO, 4mole% P2O5) and BAG61 (3mole% F added) were evaluated for cytotoxicity using Alamar Blue assay. First, composite extracts were obtained from 7 day incubations of composites in cell culture medium at 37°C. Undifferentiated pulp cells (OD-21) were exposed to dilutions of the original extracts for 3, 5, and 7 days. Then freshly cured composite disks were incubated with OD-21 cells (n=5) for 2 days. Subsequently, fresh composite disks were incubated in culture medium at 37°C for 7 days, and then the extracted disks were incubated with OD-21 cells for 2 days. Finally, fresh composites disks were light cured for 3, 5, and 20s and incubated with OD-21 cells (n=5) for 1, 3, 5, and 7 days. To verify that the three different curing modes produced different levels of degree of conversion (DC), the DC of each composite was determined by FTIR. Groups (n=5) were compared with ANOVA/Tukey's (α≤0.05).
Extracts from all composites significantly reduced cell viability until a dilution of 1:8 or lower, where the extract became equal to the control. All freshly-cured composites showed significantly reduced cell viability at two days. However, no reduction in cell viability was observed for any composite that had been previously soaked in media before exposure to the cells. Composites with reduced DC (3s vs. 20s cure), as verified by FTIR, showed significantly reduced cell viability.
The results show that the composites, independent of composition, had equivalent potency in terms of reducing the viability of the cells in culture. Soaking the composites for 7 days before exposing them to the cells suggested that the "toxic" components had been extracted and the materials were no longer cytotoxic. The results demonstrate that the cytotoxicity of composites with and without BAG must predominantly be attributed to the release of residual monomers, and not to the presence of the BAG.
测定含生物活性玻璃填料的牙科复合材料的体外细胞毒性。
使用alamar蓝测定法评估含有两种溶胶 - 凝胶生物活性玻璃BAG65（65摩尔％二氧化硅，31摩尔％氧化钙，4摩尔％五氧化二磷）和BAG61（添加3摩尔％氟）不同浓度（0、5、10和15重量％）的牙科复合材料（50:50双酚A - 双甲基丙烯酸缩水甘油酯/三乙二醇二甲基丙烯酸酯树脂：72.5重量％填料，67.5％锶玻璃和5％OX50）的细胞毒性。首先，通过在37°C的细胞培养基中对复合材料进行7天孵育获得复合提取物。将未分化的牙髓细胞（OD - 21）暴露于原始提取物的稀释液中3、5和7天。然后将新固化的复合圆盘与OD - 21细胞（n = 5）孵育2天。随后，将新鲜的复合圆盘在37°C的培养基中孵育7天，然后将提取的圆盘与OD - 21细胞孵育2天。最后，将新鲜的复合圆盘光固化3、5和20秒，并与OD - 21细胞（n = 5）孵育1、3、5和7天。为了验证三种不同的固化模式产生不同程度的转化率（DC），通过傅里叶变换红外光谱（FTIR）测定每种复合材料的DC。使用方差分析/图基检验（α≤0.05）对组（n = 5）进行比较。
所有复合材料的提取物在稀释至1:8或更低之前均显著降低细胞活力，此时提取物与对照相当。所有新固化的复合材料在两天时均显示细胞活力显著降低。然而，对于任何在暴露于细胞之前已在培养基中浸泡过的复合材料，未观察到细胞活力降低。经FTIR验证，转化率降低的复合材料（3秒与20秒固化）显示细胞活力显著降低。
结果表明，复合材料无论其组成如何，在降低培养细胞活力方面具有同等效力。在将复合材料暴露于细胞之前将其浸泡7天表明“有毒”成分已被提取，材料不再具有细胞毒性。结果表明，含或不含生物活性玻璃的复合材料的细胞毒性主要归因于残留单体的释放，而非生物活性玻璃的存在。
