Objective

Resin-based composites are known to elute leachables that include unincorporated starting materials. The objective of this work was to determine the effect of common dental monomers and initiators on Streptococcus mutans biofilm metabolic activity and biomass.

Methods

S. mutans biofilms were inoculated in the presence of bisphenol A glycerolate dimethacrylate (BisGMA), triethylene glycol dimethacrylate (TEGDMA), camphorquinone (CQ), and ethyl 4-(dimethylamino)benzoate (4E) at 0.01 μg/mL up to 500 μg/mL, depending on the aqueous solubility of each chemical. Biofilms were evaluated at 4 h and 24 h for pH (n = 3–8), biomass via crystal violet (n = 12), metabolic activity via tetrazolium salt (n = 12), and membrane permeability for selected concentrations via confocal microscopy (n = 6). Parametric and non-parametric statistics were applied.

Results

500 μg/mL TEGDMA reduced 24 h metabolic activity but not biomass, similar to prior results with leachables from undercured BisGMA-TEGDMA polymers. 50 μg/mL BisGMA reduced biofilm biomass and activity, slightly delayed the pH drop, and decreased the number of cells with intact membranes. 100 μg/mL CQ delayed the pH drop and metabolic activity at 4 h but then significantly increased the 24 h metabolic activity. 4E had no effect up to 10 μg/mL.

Significance

Monomers and initiators that leach from resin composites affect oral bacterial biofilm growth in opposite ways. Leachables, which can be released for extended periods of time, have the potential to alter oral biofilm biomass and activity and should be considered in developing and evaluating new dental materials.

中文翻译：

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牙科单体和引发剂对变形链球菌口腔生物膜的影响

客观的

已知基于树脂的复合物可洗脱包括未掺入的起始材料的可浸出物。这项工作的目的是确定常见的牙科单体和引发剂对变形链球菌生物膜代谢活性和生物量的影响。

方法

在双酚A甘油酸酯二甲基丙烯酸酯（BisGMA），三甘醇二甲基丙烯酸酯（TEGDMA），樟脑醌（CQ）和4-（二甲基氨基）苯甲酸乙酯（4E）的存在下接种变形链球菌生物膜，至多500μg / mL，取决于每种化学品的水溶性。在4 h和24 h评估生物膜的pH（n  = 3-8），通过结晶紫的生物量（n  = 12），通过四唑鎓盐的代谢活性（n  = 12）和通过共聚焦显微镜对选定浓度的膜通透性（n  = 6）。应用了参数和非参数统计。

结果

500μg/ mL TEGDMA降低了24小时的代谢活性，但没有降低生物量，这与先前固化不足的BisGMA-TEGDMA聚合物浸出液的结果相似。50μg/ mL BisGMA减少了生物膜的生物量和活性，略微延迟了pH下降，并减少了具有完整膜的细胞数量。100μg/ mL CQ在4 h延迟了pH下降和代谢活性，但随后显着增加了24 h的代谢活性。高达10μg/ mL的4E无效。

意义

从树脂复合物中浸出的单体和引发剂以相反的方式影响口腔细菌生物膜的生长。可以延长释放时间的可浸出物有可能改变口腔生物膜的生物量和活性，因此在开发和评估新的牙科材料时应予以考虑。