Dental caries is attributed to the predominance of cariogenic microorganisms. Cariogenic microorganisms are pathological factors leading to acidification of the oral microenvironment, which is related to the initiation and progression of caries. The accepted cariogenic microorganism is Streptococcus mutans (S. mutans). However, studies have found that caries could occur in the absence of S. mutans. This study aimed to assess the presence of potentially cariogenic microorganisms in human teeth biofilm. The microorganisms were isolated from human mouth and freshly extracted human maxillary incisors extracted for reasons of caries. The isolates were sorted based on their acidogenic and aciduric properties, and the S. mutans was used as the reference strain. Four potentially cariogenic strains were selected. The selected strains were identified as Streptococcus salivarius (S. salivarius), Streptococcus anginosus (S. anginosus), Leuconostoc mesenteroides (L. mesenteroides), and Lactobacillus sakei (L. sakei) through morphological analysis followed by 16S rRNA gene sequence analysis. The cariogenicity of isolates was analyzed. We show, for the first time, an association between L. sakei (present in fermented food) and dental caries. The data provide useful information on the role of lactic acid bacteria from fermented foods and oral commensal streptococci in dental caries.

中文翻译：

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人类牙齿生物膜中与龋齿相关的潜在致病微生物的分离和鉴定


龋齿是由于致龋微生物占优势。致龋微生物是导致口腔微环境酸化的病理因素，与龋病的发生和进展有关。公认的致龋微生物是变形链球菌( S. mutans )。然而，研究发现，在没有变形链球菌的情况下，龋齿也可能发生。本研究旨在评估人类牙齿生物膜中是否存在潜在致龋微生物。这些微生物是从人类口腔和因龋齿原因而摘除的新鲜拔出的人类上颌切牙中分离出来的。根据其产酸和尿酸特性对分离株进行分类，并使用变形链球菌作为参考菌株。选择了四种潜在致龋菌株。通过形态学分析和16S rRNA基因序列分析，筛选菌株分别为唾液链球菌（ S. salivarius ）、咽峡炎链球菌（ S. anginosus ）、肠膜明串珠菌（ L. mesenteroides ）和清酒乳杆菌（ L.sakei ）。分析了分离株的致龋性。我们首次证明了L.sakei （存在于发酵食品中）与龋齿之间的关联。这些数据提供了有关发酵食品中的乳酸菌和口腔共生链球菌在龋齿中的作用的有用信息。