Issa Y, Watts D C, Brunton P A, Waters C M, Duxbury A J
Turner Dental School, The University of Manchester, Manchester, UK.
Dent Mater. 2004 Jan;20(1):12-20. doi: 10.1016/s0109-5641(03)00053-8.
Substances such as monomers may be released from composite resin systems and may induce adverse effects in biological tissues. The aim of this study is to investigate the cytotoxic concentrations of resin composite monomers on cultures of human gingival fibroblasts.
A range of dilutions of five resin composite monomers (HEMA, HPMA, DMAEMA, TEGDMA, and Bis-GMA) were added to the culture medium of human gingival fibroblasts for 24 h. Their cytotoxic effects were measured by using two colorimetric functional assays, mitochondrial dehydrogenase activity (MTT) and lactate dehydrogenase activity (LDH) assay. The logP values (water/octanol partition) of test monomers were also calculated computationally.
Mitochondrial reducing activity assessed with the MTT test was inhibited by all monomers and all the monomers increased the LDH release in a reproducible dose dependent manner. A wide range of TC 50 values (concentrations altering MTT and LDH activity by 50%) (0.32-5.8 mM by MTT assay and 0.36-6.7 mM by LDH assay) was observed. Ranking of composite resin monomer cytotoxicities (TC 50) were similar for both the MTT and LDH assays, (Bis-GMA>TEGDMA>DMAEMA>HPMA >HEMA). However, the MTT assay was found to be more sensitive than the LDH assay, particularly when lower doses of the tested monomers were determined. The ranking of TC 50 concentrations correlated with the calculated logP values.
Monomers used in dental restorative materials show a variety of toxic effects on gingival fibroblasts. A combination approach using MTT and LDH assays provides valuable information about their toxic effects.
诸如单体等物质可能从复合树脂体系中释放出来，并可能在生物组织中引发不良反应。本研究的目的是调查树脂复合单体对人牙龈成纤维细胞培养物的细胞毒性浓度。
将五种树脂复合单体（甲基丙烯酸羟乙酯、甲基丙烯酸羟丙酯、甲基丙烯酸二甲氨基乙酯、双酚A-双甲基丙烯酸缩水甘油酯和二缩三乙二醇双甲基丙烯酸酯）的一系列稀释液添加到人牙龈成纤维细胞的培养基中24小时。通过两种比色功能测定法，即线粒体脱氢酶活性（MTT）和乳酸脱氢酶活性（LDH）测定法，测量它们的细胞毒性作用。还通过计算得出测试单体的logP值（水/辛醇分配系数）。
用MTT试验评估的线粒体还原活性受到所有单体的抑制，并且所有单体均以可重复的剂量依赖性方式增加LDH释放。观察到广泛的半数毒性浓度（TC50）值（使MTT和LDH活性改变50%的浓度）（MTT测定法为0.32-5.8 mM，LDH测定法为0.36-6.7 mM）。MTT和LDH测定法中复合树脂单体细胞毒性（TC50）的排名相似，（双酚A-双甲基丙烯酸缩水甘油酯>二缩三乙二醇双甲基丙烯酸酯>甲基丙烯酸二甲氨基乙酯>甲基丙烯酸羟丙酯>甲基丙烯酸羟乙酯）。然而，发现MTT测定法比LDH测定法更敏感，特别是在确定较低剂量的测试单体时。TC50浓度的排名与计算得出的logP值相关。
牙科修复材料中使用的单体对牙龈成纤维细胞表现出多种毒性作用。使用MTT和LDH测定法的联合方法提供了有关其毒性作用的有价值信息。
