Childhood is considered crucial in the establishment of future oral microbiota. However, the precise period of oral microbiota development remains unclear. This study aimed to identify the progression of oral microbiota formation in children. We longitudinally investigated the salivary microbiota of 54 children across 13 time points from 1 wk to 60 mo (5 y) old and their parents at 2 time points as a representative sample of the adult microbiota. Using next-generation sequencing, we obtained 10,000 gene sequences of the 16s rRNA V1-V2 region for each sample. The detection rate in children of 110 operational taxonomic units commonly detected in more than 85% of mothers and fathers, defined as the main constituent bacteria, was 25% at 1 wk old, increased to 80% between 6 and 18 mo old, and reached approximately 90% by 36 mo old. Early main constituent bacteria detected at 1 wk old were limited to Streptococcus, Rothia, and Gemella. At 6 to 18 mo old, the detection rates of various main constituent bacteria, including Neisseria, Haemophilus, and Fusobacterium, increased. UniFrac distance analysis showed that the oral microbiota of children approached that of adults at 6 to 18 mo old. In the weighted UniFrac distance index, unlike the unweighted index, there were no significant changes in children between 36 and 60 mo old from adults, and microbiota formation at 60 mo old was sufficiently advanced to be included within the range of adult individual differences. Our findings suggest that the initial 36 mo, particularly the period from 6 to 18 mo old, consists of a time window for oral microbiota maturation. In addition, the development of microbiota during this period may be critical for future oral disease prevention.

中文翻译：

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前 60 个月的口腔微生物群发展：一项纵向研究


童年被认为对未来口腔微生物群的建立至关重要。然而，口腔微生物群发展的确切时期仍不清楚。本研究旨在确定儿童口腔微生物群形成的进展。我们纵向调查了 54 名儿童在 1 周至 60 个月 （5） 岁的 13 个时间点的唾液微生物群及其父母在 2 个时间点的唾液微生物群，作为成人微生物群的代表性样本。使用下一代测序，我们为每个样本获得了 16s rRNA V1-V2 区域的 10,000 个基因序列。在超过 85% 的母亲和父亲（定义为主要组成细菌）中通常检测到的 110 个操作分类单元的儿童检出率在 1 周龄时为 25%，在 6 至 18 个月大时增加到 80%，到 90 个月大时达到约 36%。在 1 周龄时检测到的早期主要组成细菌仅限于链球菌、 Rothia 和 Gemella。在 6 至 18 月龄时，奈瑟菌属、嗜血杆菌属和梭杆菌属等各种主要组成菌的检出率提高。UniFrac 距离分析显示，儿童的口腔微生物群在 6 至 18 个月大时接近成人。在加权 UniFrac 距离指数中，与未加权指数不同，36 至 60 月龄儿童与成人相比没有显著变化，60 月龄微生物群形成足够先进，可纳入成人个体差异范围。我们的研究结果表明，最初的 36 个月，尤其是 6 到 18 个月大的时期，包括口腔微生物群成熟的时间窗口。此外，在此期间微生物群的发展可能对未来的口腔疾病预防至关重要。