远缘链球菌与乳牙龋病关系的研究

The study of the relation between streptococcus sobrinus and primary teeth caries

目的：探讨远缘链球菌与乳牙龋病的关系。方法：采有ＴＹＣＳＢ培养基作细菌筛选，运用分子遗传学手段即ＤＮＡ的Ｇ＋ Ｃ ｍｏｌ％ 测定作最终鉴定。结果：患龋儿童组与无龋儿童组变形链球菌检出率有显著差异（Ｐ＜０ ．０１），远缘链球菌检出率有显著差异（Ｐ＜ ０．０５） ；患龋儿童组中能同时检出变形链球菌和远缘链球菌的群体，其龋失补牙数、龋失补牙面数及平滑面龋数均与只能检出变形链球菌的群体有显著差异（ Ｐ＜ ０．０１） 。结论：变形链球菌是龋病的主要致病菌，远缘链球菌对龋病过程有协同作用，与乳牙平滑面龋的发生、发展有关。

Aim:To determine the relationship of streptococcus sobrinus with rampant caries and smooth-surface caries of primary teeth. Methods: Dental plaque samples of fourty carious children and thirty caries-free children were cultured and studied by using their DNA base composition as a golden standard. Results: The positive rate of streptococcus sobrinus of case group was 20%. The positive rate of streptococcus sobrinus of control group was 3.3% , there was significant difference between them ( P <0.05). Compared with those of the streptococcus mutans group, dmft, dmfs and somooth-surface caries of the streptococcus mutans and streptococcus sobrinus group were statistically significant( P <0.01). Conclusions: Streptococcus sobrinus cooperated with streptococcus mutans in caries process and it has relation with the rampant caries and smooth-surface caries of primary teeth.