Bansal Kalpana, Chaudhary Rama, Mathur Vijay P, Tewari Nitesh
Department of Pedodontics and Preventive Dentistry, Centre for Dental Education and Research, All India Institute of Medical Sciences, New Delhi, India.
Department of Microbiology, Centre for Dental Education and Research, All India Institute of Medical Sciences, New Delhi, India.
Indian J Dent Res. 2020 May-Jun;31(3):420-425. doi: 10.4103/ijdr.IJDR_39_19.
Although Streptococcus mutans has been implicated as the major etiologic agent in the development of dental caries, however, this organism has not been found to be present in all children with caries. Thus it remains to be elucidated whether a single or specific consortium of bacteria is responsible for the caries process. The aim of this study is to evaluate the oral microflora of Indian children suffering from dental caries and to compare the same in children with no caries.
The study was carried out on 67 out-patient 2-14 years old children who reported to the department of Paediatric Dentistry. Dental plaque samples from superficial and deep carious lesions and caries free surfaces in caries active children (n = 35) were collected using a sterile excavator in storage vials and subjected to various conventional and molecular microbial techniques. Caries free children (n = 32), who did not have any carious lesion served as controls. The data obtained was subjected to Pearson's Chi Square/Fischer's Exact tests to determine the statistical difference between the microflora of groups.
Main organisms isolated were: Streptococcal species mainly S anginosus, S salivarius, S gordonii: Lactobacilli spp; Coagulase negative Staphylococci, Staph epidermidis, Staph aureus. Other organisms such as Klebsiella spp, Acinetobacter, Enterococcus, E coli could also be found. There was a statistical difference in the frequency of isolation of non-mutans Streptococcal species (P = 0.008) and Lactobacilli species (P = 0.0001) in the two groups.
The study suggests that caries activity in this population of children is associated with a diverse microbial flora without detectable S mutans. Main organisms associated with dental caries in this population are: Gram-positive cocci and bacilli mainly the non-mutans Streptococcus and Lactobacilli. Frequent consumption of sugar containing food promotes the presence and growth of cariogenic organisms.
虽然变形链球菌被认为是龋齿发生的主要病原体，然而，并非所有患龋齿的儿童体内都能检测到这种微生物。因此，龋齿过程究竟是由单一细菌还是特定的细菌组合引起仍有待阐明。本研究旨在评估患有龋齿的印度儿童的口腔微生物群，并与无龋齿儿童的口腔微生物群进行比较。
本研究针对67名2至14岁到儿童牙科就诊的门诊患儿开展。使用无菌挖匙从35名患龋活跃儿童的浅表和深层龋损以及无龋表面采集牙菌斑样本，置于储存瓶中，并采用各种传统和分子微生物技术进行检测。32名无龋儿童作为对照组，他们没有任何龋损。对获得的数据进行Pearson卡方检验/Fisher精确检验，以确定两组微生物群之间的统计学差异。
分离出的主要微生物有：链球菌属，主要是咽峡炎链球菌、唾液链球菌、戈登链球菌；乳杆菌属；凝固酶阴性葡萄球菌，表皮葡萄球菌、金黄色葡萄球菌。还能发现其他微生物，如克雷伯菌属、不动杆菌属、肠球菌属、大肠杆菌。两组之间非变形链球菌属（P = 0.008）和乳杆菌属（P = 0.0001）的分离频率存在统计学差异。
该研究表明，这群儿童的龋活性与多种微生物群有关，未检测到变形链球菌。该群体中与龋齿相关的主要微生物是：革兰氏阳性球菌和杆菌，主要是非变形链球菌和乳杆菌。频繁食用含糖食物会促进致龋微生物的存在和生长。
