Investigation of visually impaired schoolchildren's dental health and salivary microbiota characteristics in Guangzhou, China

Abstract

Background Reports indicate that the prevalence of visual impairment (VS) among children in China is on the rise. The oral microbiome plays an essential role in maintaining oral homeostasis and health. The primary objective was to examine the oral health and their oral hygiene habits of VS children in Guangzhou. The secondary objective was to explore the differences in the saliva samples microbiota (SM) between HS (health visual children) and VS children. Method 101 VS children were chosen to have their oral health examined and their oral hygiene habits surveyed. The oral microbiota was profiled from saliva samples of 20 VS children and 20 healthy visual (HS) children in the Guangzhou population, and 16s rRNA V3-V4 region were sequenced using the Illumina MiSeq platform. The operational taxonomic units (OTUs) were clustered using QIIME and the statistical analysis was performed by R. Results Oral hygiene is inadequate among the 101 VS children age from 6-16, who have an exceptionally high caries rate of 92.1%. There was no statistically significant distinction observed in the composition of the salivary microbial community between the two groups. HS children had a higher abundance of Firmicutes, Patescibacteria, and Spirochaetes at the phylum level, and Bacilli, Negativicutes, and Saccharimonadia at the classes level, and Streptococcus at the genus level. In contrast, VS children had more Actinobacteria, Bacteroidetes, Proteobacteria, and Fusobacteriota at the phylum level, and Actinobacteria, Bacteroidia, Gammaproteobacteria, Fusobacteriia, and Clostridia at the classes level, and Rothia, Neisseria, Veillonella, Prevotella_7, Actinomyces, Leptotrichia, and lactobacillales at the genus level. Notably, Actinobacteria was significantly positively correlated with gingivitis and dental caries. Additionally, Actinobacteria salivarius, within the phylum Actinobacteria, was substantially more abundant in VS children. Conclusion The study highlights the importance of oral health care for visually impaired schoolchildren in Guangzhou. It provides valuable insights into the salivary microbiota characteristics of this population and suggests potential targets for intervention to improve their oral health status.