高发龋和无龋儿童菌斑中变形链球菌及远缘链球菌的任意引物PCR检测  

Arbitrarily primed-PCR detection of Streptococcus mutans and Streptococcus sobrinus in dental plaque of children with high dmft and no caries

作　　者：支清蕙[1] 林焕彩[1] 张蓉[1] 廖义东[1] 涂家珍[1] 

机构地区：[1]中山大学光华口腔医学院口腔预防科,广州510055

出　　处：《中华口腔医学杂志》2007年第4期219-222,共4页Chinese Journal of Stomatology

基　　金：广东省自然科学基金(04009344)

摘　　要：目的采用任意引物聚合酶链反应(arbitrarily primed-polymerase chain reaction,AP-PCR)法探讨高发龋和无龋儿童牙菌斑致龋菌的检出情况,分析变形链球菌及远缘链球菌与乳牙龋齿发生的关系。方法从20例高发龋患儿和20名无龋儿童的牙菌斑中分离、鉴定变形链球菌和远缘链球菌,以 Shiroza 的 DNA 提取方法提取细菌基因组 DNA,以形态学、生化和 AP-PCR 的方法鉴定变形链球菌和远缘链球菌。结果 AP-PCR 法检测发现高发龋患儿变形链球菌和远缘链球菌的检出率分别为100%和40%,而无龋儿童两种细菌的检出率分别为75%和5%,差异有统计学意义。结论用 AP-PCR 法检测发现高发龋患儿变形链球菌和远缘链球菌的检出率均明显高于无龋儿童,口腔中定植的变形链球菌和远缘链球菌是乳牙龋高发的危险因素。Objective To isolate and identify Streptococcus mutans（Sm） and Streptococcus sobrinus （Ss） in dental plaque of children with high dmft and no caries by selective medium, biochemical methods and arbitrarily primed-polymerase chain reaction（AP-PCR）. Methods A total of 401 3-4-year-old children from seven kindergardens were recruited using cluster sampling and their dental caries status were examined. From 30% of children with the highest draft score （dmft≥5）, 20 children were chosen randomly as test group and 20 age and gender-matched caries-free children were selected as control. Plaque samples were collected from buccal surfaces of the molars and plated onto TYCSB plate. Sm and Ss were primarily identified by colony morphology and biochemical characteristics. Then chromosomal DNA of the strains was isolated and Sm or Ss were confirmed by AP-PCR. Results The proportion positive for Sm and Ss in children with high dmft was 100% and 40% respectively while that in caries-free children was 75% and 5% by AP-PCR analysis. The differences were statistically significant between the two groups. Conclusions The proportions positive for Sm and Ss detected by AP-PCR method were significantly higher in children with high draft than in caries-free children and it is a risk factor for high draft in deciduous teeth harboring Sm and Ss.

关 键 词：牙 乳 龋齿 链球菌 变异 远缘链球菌 

分 类 号：R450[医药卫生—治疗学]