支架用钴铬合金表面镀金对变异链球菌粘附的影响

Effect of gold-plating treatment of Co-Cr alloy on adhesion of Streptococcus mutans

目的研究支架用钴铬合金表面镀金对变异链球菌粘附能力的影响。方法将义齿支架用钴铬合金制作成试件,随机分为实验组和对照组,每组30块。实验组表面镀金处理,对照组表面不做任何处理。用SJ-201便携式表面粗糙度仪检测两组粗糙度差异。通过细菌体外粘附实验分析4h、8h、12h时每组试件表面变异链球菌的粘附量。通过测定粘附于试件表面的变异链球菌表达CAT(报告基因产物)的活性,确定镀金处理对变异链球菌合成细胞外多糖能力的影响。结果实验组试件表面变异链球菌的粘附量均少于对照组(P<0.05);其表达CAT的能力明显低于对照组(P<0.05)。结论钴铬合金表面镀金可有效抑制变异链球菌的粘附,作用机制可能与其抑制gtf B基因表达有关。

Objective To investigate the effect of gold-plating on Co-Cr alloy used for fabricating denture framework on adhesion of Streptococcus mutans. Methods Sixty pieces of specimens made by Co-Cr alloy were randomly divided into the experimental group and the control group. Each group contained 30 pieces. The tested specimens were plated gold on the surface, while the control group received no treatment. The surface roughness of the two groups was measured by SJ-201. The number of bacteria adhered to the surface was assayed by means of colony forming unit （CFU） method at adhesion periods of 4h ,8h, 12h. Finally, the effect of the gold-plated processing on the synthesis of extracellular polysaccharide of S. mutarts was determined by measuring the activity of CAT. Results The amount of the microbe attached to the surface of experimental group was significantly decreased compared with that of the control group （ P 〈 0.05 ）. The CAT activity of the microbe in experimental group was also significantly reduced （P 〈 0.05 ）. Cortdusion The gold-plating on Co-Cr alloy could reduce the adhesion of S. mutans and the underlying mechanism might be related to the inhibition of the expression of genes coding for extracellular polysaccharide synthetases such as gtfB.