含长链烷基季铵盐的纳米抗菌无机填料的合成及其在牙科复合树脂中的应用研究

目的 设计合成新型的含长链烷基季铵盐的纳米抗菌无机填料，以赋予牙科复合树脂更优良的抗菌性能。方法 在分子设计和筛选的基础上，制备了长链烷基季铵盐修饰的纳米抗菌二氧化硅填料，并对填料的抗菌性能进行评价。为进一步提高抗菌填料与树脂的结合力，采用硅烷偶联剂对抗菌填料表面进行了处理，并用红外光谱法对其结构特征进行分析；然后将新型纳米抗菌无机填料加入牙科复合树脂中，观察其在复合树脂基体中的分散情况，同时与商品化的Tetric N-Ceram纳米瓷化复合树脂进行对比；并以变异链球菌为对象，研究复合树脂的抗菌性能。结果 长链烷基季铵盐成功接枝到纳米二氧化硅颗粒表面；新型纳米抗菌无机填料的抗菌性能优于含短链烷基季铵盐的抗菌无机填料；偶联处理后的纳米抗菌无机填料在树脂基体中分散均匀，与树脂结合紧密，与Tetric N-Ceram纳米瓷化复合树脂类似；改性后的复合树脂抗菌性能良好。结论 含长链烷基季铵盐的纳米抗菌无机填料抗菌性能良好，经过表面偶联处理后可以很好地与牙科复合树脂共混，提高了牙科复合树脂的抗菌性能。

Synthesis of a nano-antibacterial inorganic filler containing a quaternary ammonium salt with long chain alkyl and ;its effect on dental resin composites

Objective This study aimed to synthesize a novel nano-antibacterial inorganic filler that contains a quaternary ammonium salt with long chain alkyl and to report the antibacterial property of dental resin composites. Methods A novel nano-antibacterial inorganic filler that contains a quaternary ammonium salt with long chain alkyl was synthesized based on previous research. The antibacterial property of the filler was measured. The surface of the novel nano-antibacterial inorganic filler was modified by a coupling agent to achieve a good interfacial bonding between the filler and the resin matrix. Infrared spectrum analysis was carried out. The modified novel nano-antibacterial inorganic fillers were then incorporated into the dental resin matrix. The dispersion of the fillers was observed and compared with those incorporated into Tetric N-Ceram, a commercial resin composite, under a scanning electron microscope. Streptococcus mutans was used in testing the antibacterial property of the dental resin composites. Results A quaternary ammonium salt with a long chain alkyl was successfully grafted onto the surface of nano-silica particles. The novel nano-antibacterial inorganic filler that contains quaternary ammonium salt with a long chain alkyl showed stronger antibacterial efficacy than the antibacterial inorganic filler that contains quaternary ammonium salt with a short chain alkyl. The modified novel antibacterial inorganic fillers displayed a homogeneous dispersion in the resin composite bulk and combined closely with the resin matrix, similar to the Tetric N-Ceram. The resin com-posites that contain novel antibacterial inorganic fillers showed stronger antibacterial effect on Streptococcus mutans compared with the control group. Conclusion The novel nano-antibacterial inorganic filler that contains a quaternary ammonium salt with long chain alkyl showed a strong antibacterial property. It also exhibited good compatibility with the dental resin matrix after undergoing coupling treatment.