四甲基偶氮唑盐法评价牙体修复性纳米羟基磷灰石复合材料的体外细胞毒性

背景：越来越多的新型材料被纳入口腔领域应用的视野,对生物材料进行生物相容性评价是进入临床试验前的重点研究内容。目的：通过体外细胞毒性实验评价自制牙体修复性纳米羟基磷灰石复合材料的生物相容性。方法：根据ISO标准,采用四甲基偶氮唑盐比色法行体外细胞毒性实验,阴性对照组为DMEM培养液,阳性对照组为含有0.1%苯酚的DMEM培养液,实验组为受试材料的浸提液。测试人牙龈成纤维细胞在牙体修复性纳米羟基磷灰石复合材料浸提液中培养1,3,5d的吸光度值,观察细胞形态变化,计算细胞相对增殖率,判断细胞毒性的级别。结果与结论：实验组体外细胞毒性实验吸光度值均与阴性对照组差异无显著性意义（P〉0.05）,与阳性对照组差异有显著性意义（P〈0.01）,自制牙体修复性纳米羟基磷灰石复合材料体外细胞毒性级别为0～1级,初步认为其具有良好的生物相容性。

In vitro cytotoxicity of the self-made light-cured nano-hydroxyapatite composite for tooth restoration evaluated by MTT assay

BACKGROUND：More and more new materials are introduced in the field of oral application,and the evaluation of biomaterial biocompatibility is a key step before the clinical application OBJECTIVE：To evaluate the biocompatibility of the self-made light-cured nano-hydroxyapatite composite for tooth restoration through in vitro cytotoxic experiments.METHODS：According to ISO standards,in vitro cytotoxicity test（MTT assay） was used to test the absorbance value of human gingival fibroblasts in the self-made light-cured nano-hydroxyapatite composite for tooth restoration extracts（experimental group） of 1,3,5 days,to observe changes in cell morphology,to calculate the relative growth rate,and to determine the cytotoxicity grade.Cells in negative control group were cultured in Dulbecco’s modified Eagle’s medium,while those in positive control group were cultured in Dulbecco’s modified Eagle’s medium containing 0.1% phenol.RESULTS AND CONCLUSION：The absorbance value in the experimental group was similar to that in the negative control group（P 〉 0.05）,but significantly different from that in the positive control（P 〈 0.01）,which indicated that the materials tested were safe to the human gingival fibroblasts.It is preliminarily estimated that nano-hydroxyapatite composite is a safe material for dental clinical application with good biocompatibility.