Folkhälsan Research Center, Helsinki, Finland.
Department of Public Health, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
Sci Rep. 2021 Feb 24;11(1):4424. doi: 10.1038/s41598-021-83846-1.
Dental caries is a biofilm-mediated, dynamic disease with early onset. A balanced salivary microbiota is a foundation of oral health, while dysbiosis causes tooth decay. We compared the saliva microbiota profiles in children with and without caries. The study consisted of 617 children aged 9-12 years from the Finnish Health in Teens (Fin-HIT) study with available register data on oral health. Caries status was summarised based on Decayed, Missing, and Filled Teeth (DMFT) index in permanent dentition. The children were then classified into the following two groups: DMFT value ≥ 1 was considered as cavitated caries lesions (hereafter called 'caries') (n = 208) and DMFT = 0 as 'cavity free' (n = 409). Bacterial 16S rRNA gene (V3-V4 regions) was amplified using PCR and sequenced by Illumina HiSeq. The mean age (SD) of the children was 11.7 (0.4) years and 56% were girls. The children had relatively good dental health with mean DMFT of 0.86 (1.97). Since sex was the key determinant of microbiota composition (p = 0.014), we focused on sex-stratified analysis. Alpha diversity indexes did not differ between caries and cavity free groups in either sexes (Shannon: p = 0.40 and 0.58; Inverse Simpson: p = 0.51 and 0.60, in boys and girls, respectively); neither did the composition differ between the groups (p = 0.070 for boys and p = 0.230 for girls). At the genus level, Paludibacter and Labrenzia had higher abundances in the caries group compared to cavity free group in both sexes (p < 0.001). Taken together, there were minor differences in saliva microbiota between children with and without caries. Potential biomarkers of caries were the sugar metabolisers Paludibacter and Labrenzia. These bacteria presumably enhance salivary acidification, which contributes to progression of dental caries. The clinical relevance of our findings warrants further studies.
龋齿是一种以生物膜为介导的、早期发病的动态疾病。平衡的唾液微生物群是口腔健康的基础，而失调会导致龋齿。我们比较了有和无龋齿儿童的唾液微生物群谱。这项研究包括来自芬兰青少年健康研究（Fin-HIT）的 617 名 9-12 岁的儿童，这些儿童的口腔健康有可用的登记数据。龋齿状况根据恒牙列中的龋失补牙数（DMFT）指数进行总结。然后，将儿童分为以下两组：DMFT 值≥1 被认为是有腔龋齿病变（以下简称“龋齿”）（n=208），DMFT=0 为“无腔”（n=409）。使用 PCR 扩增细菌 16S rRNA 基因（V3-V4 区），并通过 Illumina HiSeq 进行测序。儿童的平均年龄（SD）为 11.7（0.4）岁，56%为女孩。这些儿童的牙齿健康状况相对较好，DMFT 平均值为 0.86（1.97）。由于性别是微生物群组成的关键决定因素（p=0.014），因此我们专注于性别分层分析。在男女两性中，龋齿组和无腔组的 alpha 多样性指数无差异（Shannon：p=0.40 和 0.58；Inverse Simpson：p=0.51 和 0.60）；两组之间的组成也没有差异（男孩 p=0.070，女孩 p=0.230）。在属水平上，与无腔组相比，男女两性中龋齿组的 Paludibacter 和 Labrenzia 丰度更高（p<0.001）。总之，有龋齿和无龋齿儿童的唾液微生物群之间存在细微差异。龋齿的潜在生物标志物是糖代谢物 Paludibacter 和 Labrenzia。这些细菌可能会增强唾液酸化，从而促进龋齿的进展。我们研究结果的临床意义需要进一步研究。
