Meng Junquan, Yang Huichuan, Cao Man, Li Lei, Cai Qing
State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, PR China.
Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029, PR China.
Mater Sci Eng C Mater Biol Appl. 2017 Sep 1;78:413-419. doi: 10.1016/j.msec.2017.04.008. Epub 2017 Apr 4.
Cytotoxicity of photocurable composite resins is a key issue for their safe use in dental restoration. Curing kinetic and elution behaviors of the composite resin would have decisive effects on its cytotoxicity. In this study, composite resins composed of bisphenol-glycidyl dimethacrylate (Bis-GMA), triethyleneglycol dimethacrylate (TEGDMA), camphorquinone (CQ), N,N-dimethylaminoethyl methacrylate (DMAEMA) and barium glass powders were prepared by setting the photoinitiators CQ/DMAEMA at 0.5wt%, 1wt% or 3wt% of the total weight of Bis-GMA/TEGDMA. The ratio of Bis-GMA/TEGDMA was 6:4, the ratio of CQ/DMAEMA was 1:1, and the incorporated inorganic powder was 75wt%. Then, curing kinetics were studied by using real-time Fourier transform infrared spectroscopy (FTIR) and photo-DSC (differential scanning calorimeter). Elution behaviors in both ethanol solution and deionized water were monitored by using liquid chromatogram/mass spectrometry (LC/MS). Cytotoxicity was evaluated by in vitro culture of L929 fibroblasts. Finally, they were all analyzed and correlated in terms of initiator contents. It was found that the commonly used 0.5wt% of photoinitiators was somewhat insufficient in obtaining composite resin with low cytotoxicity.
光固化复合树脂的细胞毒性是其在牙科修复中安全使用的关键问题。复合树脂的固化动力学和洗脱行为对其细胞毒性具有决定性影响。在本研究中，通过将光引发剂樟脑醌（CQ）/甲基丙烯酸N,N-二甲氨基乙酯（DMAEMA）设定为双酚-二甲基丙烯酸缩水甘油酯（Bis-GMA）/三乙二醇二甲基丙烯酸酯（TEGDMA）总重量的0.5wt%、1wt%或3wt%，制备了由Bis-GMA、TEGDMA、CQ、DMAEMA和钡玻璃粉组成的复合树脂。Bis-GMA/TEGDMA的比例为6:4，CQ/DMAEMA的比例为1:1，掺入的无机粉末为75wt%。然后，使用实时傅里叶变换红外光谱（FTIR）和光差示扫描量热仪（photo-DSC）研究固化动力学。通过液相色谱/质谱（LC/MS）监测在乙醇溶液和去离子水中的洗脱行为。通过L929成纤维细胞的体外培养评估细胞毒性。最后，根据引发剂含量对它们进行了全面分析并建立了相关性。结果发现，常用的0.5wt%光引发剂在获得低细胞毒性复合树脂方面略显不足。
