老化处理对含新型纳米抗菌无机填料复合树脂相关性能的影响

Effect of water-aging on resin composite containing novel antibacterial inorganic nano-fillers

目的:探讨老化处理后,含新型纳米抗菌无机填料复合树脂相关性能的变化。方法:制备含长链烷基季铵盐的纳米抗菌二氧化硅填料,经表面偶联处理后,以10%的质量分数添加到复合树脂中,形成抗菌复合树脂,同时选取无抗菌性的商品化复合树脂Tetric N-Ceram作为对照。复合树脂试件在37℃蒸馏水中老化处理不同时间。用三点弯曲试验来检测其力学性能的变化。通过人牙菌斑生物膜菌落计数、乳酸代谢分析及活/死细菌染色等手段来评价抗菌性能的改变。结果:浸泡30d后,对照组和实验组复合树脂力学性能下降明显(P<0.05),而后随着老化时间的延长,性能下降不明显(P>0.05);随着老化时间的延长,实验组复合树脂对人牙菌斑生物膜的代谢仍然产生明显的抑制作用,显示出良好的抗菌性能(P<0.05)。结论:老化处理后,抗菌复合树脂力学性能下降而抗菌性没有明显的变化。

Objective： To assess the effect of water-aging on resin composite containing novel antibacterial inorganic nano-fillers. Methods： In present study novel nano-antibacterial inorganic filler containing long chain alkyl quaternary ammonium salt was synthesized according to methods introduced in the previous research. This novel nano-antibacterial inorganic fillers were modified by coupling agent and then added into resin composite at mass fractions of 10% while a commercial composite named Tetric N-Ceram served as control. The samples were water-aged in 37℃ distilled water for different periods. A flexural test was used to measure resin composite mechanical properties. A dental plaque microcosm biofilm model with human saliva as inoculum was formed. Colony-forming unit（CFU） counts, lactic acid production and live/dead assay of biofilm on resin composite were measured to test the resin composite antibacterial properties. Results： The mechanical properties decreased significantly after the composite has been water-aged for 30 days（P〈0.05）, and there was no significant reduction from then on（P〉 0.05）. The antibacterial resin composite exhibited strong inhibition effect on the biofilm metabolic activity vs. water-aging time from 1 d to 180 days（P〉0.05）, indicating the composite could still be able to have promising antibacterial properties even after water-aged. Conclusion： Water-aging could decrease this novel antibacterial resin composite mechanical properties while had no adverse effect on its antibacterial properties.