Banas Jeffrey A, Zhu Min, Dawson Deborah V, Blanchette Derek R, Drake David R, Gu Hongjie, Frost Ryan, McCaulley Grant, Levy Steven M
Iowa Institute for Oral Health Research, University of Iowa College of Dentistry, Iowa City, IA, USA;
Iowa Institute for Oral Health Research, University of Iowa College of Dentistry, Iowa City, IA, USA.
J Oral Microbiol. 2016 Oct 26;8:32940. doi: 10.3402/jom.v8.32940. eCollection 2016.
Non-mutans low pH oral streptococci are postulated to contribute to caries etiology.
This study was undertaken to investigate whether the acidogenicity and acid tolerance of clinical strains of and correlate with health or early-stage enamel caries.
and were isolated from plaque samples taken from the occlusal surfaces of second molars sampled at two different visits 4 years apart. All sites were sound at Visit 1; subjects were segregated into one of three groups based on the status of the site at Visit 2 and caries elsewhere in the dentition. Strains of and were evaluated for acidogenicity and acid tolerance, and the results correlated with the clinical status of the sites from which they were isolated. Mutans streptococci (MS) isolated from the plaque samples were also quantified, and the presence or absence of growth on pH 5.5 media or on media selective for bifidobacteria was recorded.
No significant positive correlations were found between the acidogenicity properties of the and clones and caries at either visit. Similar results were obtained for acid tolerance of clones but were inconclusive for clones. A statistically significant positive correlation between MS levels and caries (or future caries) was evident at both visits, but there were no statistical correlations with the growth on pH 5.5 media or media selective for bifidobacteria.
The low pH potential likely varies considerably among oral streptococcal species and is least likely to be found among strains of . Accordingly, the concept and constitution of 'low pH streptococci' may need to be re-evaluated.
非变形低pH口腔链球菌被认为与龋齿病因有关。
本研究旨在调查和临床菌株的产酸性和耐酸性是否与健康状况或早期釉质龋相关。
和从相隔4年的两次不同就诊时采集的第二磨牙咬合面菌斑样本中分离得到。在第一次就诊时所有部位均健康；根据第二次就诊时该部位的状况以及牙列中其他部位的龋齿情况，将受试者分为三组之一。对和菌株的产酸性和耐酸性进行评估，并将结果与分离出这些菌株的部位的临床状况相关联。还对从菌斑样本中分离出的变形链球菌（MS）进行了定量，并记录其在pH 5.5培养基或双歧杆菌选择性培养基上是否生长。
在两次就诊时，和克隆的产酸特性与龋齿之间均未发现显著正相关。克隆的耐酸性也得到了类似结果，但克隆的结果尚无定论。在两次就诊时，MS水平与龋齿（或未来龋齿）之间均存在统计学上显著的正相关，但与在pH 5.5培养基或双歧杆菌选择性培养基上的生长无统计学相关性。
口腔链球菌物种间的低pH潜力可能差异很大，且在菌株中最不可能发现。因此，“低pH链球菌”的概念和构成可能需要重新评估。
