烤瓷冠修复初期表面细菌黏附的实验研究

目的:分析烤瓷冠修复初期变形链球菌(Ua)、内氏放线菌(An)和牙龈卟啉单胞菌(Pg)在修复体表面黏附的先后顺序和定植数量,为临床上选择合适的修复体和尽可能减少细菌在修复体表面附着和定植提供参考。方法:将烤瓷材料制作完成并逐级打磨抛光后,和釉质一起放入分别含有上述3种细菌的混合培养基中厌氧培养,在6、12和24 h3个时间段,分别定量检测试件表面黏附的细菌数量以及液体培养基中的细菌数量,采用SPSS 6.0软件包对数据进行统计学处理。结果:2种试件表面及液体培养基中均未检测到Pg。前6 h,Ua/An在2组试件表面的附着烤瓷组少于釉质组;12 h后,An在烤瓷表面增加最快,釉质次之;24 h后,烤瓷组和釉质组的Ua/An几乎无变化。结论:3种细菌混合培养时,Pg受到强烈抑制。烤瓷修复初期,不需考虑对牙龈卟啉单胞菌的抑制。如要抑制Ua/An,对烤瓷修复体而言,前12 h是关键期。烤瓷冠是可优先选择的良好修复体。

Analysis of the bacterium adhesions on the surface of PFM materials in vitro

PURPOSE: With the observation of bacterial adhesion on the surface of the PFM and enamel,we analyzed the sequence of these adhesions and offer options for prevention of their occurrence.METHODS: The specimen made of PFM were polished step by step.Then they,along with the enamel were put into the liquid BHI culture medium containing Ua,Pg and An.After 6h,12h and 24h the adhesive microbial amount in the culture medium was determined by counting formation unit.F test was used to analyze the results with SPSS 6.0 software package.RESULTS: Pg was found neither on the surface of specimen,nor in the liquid BHI culture medium;The value of Ua/An in the groups of PFM was less than that in the groups of enamel within 6 hours.And 12 hours later,the maximal increment of An was seen in the group of PFM.And there was no change in the groups of PFM and enamel during 12 and 24 hours.CONCLUSIONS: Pg was inhibited when these bacteria were cultured together.If we wish to prevent the adhesion of Ua and An,the first 12 hours is the critical period for PFM.Given the result of the analysis,PFM is a good restoration.