表兄链球菌的检测与儿童猛性龋的关系

目的：探讨表兄链球菌(Streptococcus sobrinus,S. sobrinus)与儿童猛性龋的关系。方法：根据前期郑州市区猛性龋调查结果，随机抽样选择3～5岁儿童66例，其中猛性龋、普通高龋及无龋组各22例。采用TYCSB培养基作变形链球菌(Streptococcus mutans, S. mutans )及S. sobrinus初步筛选，结合生理生化鉴定，并采用聚合酶链反应作最终鉴定。采用 SPSS10.0软件包对实验组与对照组S.mutans和S.sobrinus的检出率进行χ²检验，组间均数作t检验。结果： S. sobrinus在各组儿童牙菌斑中均不能脱离S. mutans而单独检出，猛性龋组S. mutans检出率高于高龋组，差异无显著性(P>0.05)，而2组儿童S. sobrinus检出率的差异有显著性(P<0.05)；猛性龋组与无龋组S. mutans检出率差异显著(P<0.05)，S. sobrinus检出率差异显著(P< 0.01)。同时检出S. mutans和S. sobrinus的样本，其猛性龋的发生率及龋失补牙数、龋失补牙面数和平滑面龋均数与只能检出S. mutans及2种细菌均不能检出的样本的差异有显著性(P< 0.01)。结论：S. mutans与S. sobrinus是儿童猛性龋的主要致病菌，S. sobrinus与儿童猛性龋的发生有关。S. sobrinus对儿童猛性龋的发生、发展具有协同作用。

The relationship between Streptococcus sobrinus and rampant caries in children

PURPOSE: To explore the relations between Streptococcus sobrinus (S. Sobrinus) and rampant caries in children. METHODS: Based on previous investigation result for rampant caries in Zhengzhou city, 66 children aged 3-5 years were selected by random sampling, and divided into 3 groups of rampant caries, high dental caries and no caries, 22 cases in each group. The final identification of S. mutans and S. sobrinus were performed after using culture medium TYCSB to operate preliminary screening of Streptococcus mutans (S. Mutans) and S. Sobrinus with polymerase chain reaction(PCR) combined with physiological and biochemical identification. SPSS10.0 software package was used to compare the detection rate and mean values of S.mutans and S.sobrinus in the experimental group and the control group. RESULTS: It was found that single S. sobrinus without S. mutans was not detected from dental plaque in each group. The detection rate of S. mutans in group of rampant caries was higher than in group of high dental caries, but there was no significant difference (P>0.05). The difference of detection rate of S. sobrinus between the two groups and the detection rate of S. mutans between group of rampant caries and group without caries was significant(P<0.05). The difference of the detection rate of S. sobrinus between group of rampant caries and group without caries was also significant(P<0.01). The incidence of rampant caries, DMFT, DMFS, smooth-surface caries among the sample with both of S. sobrinus and S. mutans detected and the sample only with S. mutans and the sample without S. sobrinus and S. mutans were significantly different (P<0.01). CONCLUSIONS: The main pathogenic bacteria of rampant caries in children are S. mutans and S. sobrinus. The incidence of rampant caries was related to S. sobrinus, which had synergic effect on the occurrence and development of rampant caries in children.