Quantitative assessment of salivary oral bacteria according to the severity of dental caries in childhood

Abstract

This study aimed to assess differences in selected oral bacteria in children according to the severity of dental caries. One hundred and thirty-six children, 36-60 months old were divided into three groups according to caries status: caries-free (CF) (n=47), early childhood caries (ECC) (n=40) and severe-early childhood caries (S-ECC) (n=49). Saliva was collected for detection and quantification of selected oral streptococci, Actinomyces naeslundii, Lactobacillus spp., Bifidobacterium spp., and Scardovia wiggsiae by quantitative-polymerase chain reaction. The results showed that the detection and quantitative levels of S. mutans, S. sobrinus, Bifidobacterium spp. and S. wiggsiae were significantly higher in S-ECC children compared to CF and ECC children, while for S. salivarius were significantly higher in CF compared to ECC and S-ECC children. There was no statistical difference among the clinical groups for S. mitis, S. oralis, A. naeslundii and Lactobacillus spp. levels and detection. S-ECC children had a lower monthly family income, started tooth brushing later and were breastfeed for a longer duration compared to CF children. S. mutans levels were positively correlated with S. wiggsiae and Bifidobacterium spp. levels, lower mother's education and child bottle-feeding before sleeping and negatively correlated with S. salivarius. It was concluded that in addition to S. mutans, other bacterial species, including bifidobacteria, Scardovia wiggsiae and S. sobrinus, are associated with severity of early childhood caries, although their role in the progress of dental caries remains unclear.

Sugar Metabolism of Scardovia wiggsiae, a Novel Caries-Associated Bacterium

“…A previous study found that mutans streptococci, which have high cariogenic potential, can reduce the environmental pH to 3.5 (Aizawa et al, 2009), which suggests that the acid productivity and acid tolerance of S. wiggsiae are equivalent to those of S. mutans. This might be one of the reasons why S. wiggsiae is frequently detected in caries lesions (Tanner et al, 2012;Colombo et al, 2017;Chandna et al, 2018). As was reported for Bifidobacterium dentium and Bifidobacterium longum, acetic acid was the main acidic end-product by S. wiggsiae (Table 1), whereas many cariesassociated bacteria, such as mutans streptococci, predominantly produce lactic acid (Manome et al, 2019).…”

Functional profiles of coronal and dentin caries in children

“…HOT 448 [34] observed in dentin caries in the current report. S. wiggsiae is a relatively newly recognized species that has been detected in caries in several reports from the US [5], Europe [35] and Brazil [36]. Other highly acidogenic, lactate-producing species in dentin included A. rimae and A. parvulum [37] although the acid tolerance of these species is unknown.…”

Quantitative Analysis of Salivary Oral Bacteria Associated with Severe Early Childhood Caries and Construction of Caries Assessment Model

“…Two pairs of primers (for S. mutans and L. fermentum) were used based on the published primer protocols ( Table 1). Another two pairs of new primers (for P. pallens and P. denticola) were designed using AlleleID 6.0 (Premier Biosoft, Palo Alto, CA, USA) for qPCR and then analyzed in BLASTn (https://blast.ncbi.nlm.nih.gov/Blast.cgi?PAGcE_TYPE=BlastSearch) 1 . Species specificity for the primers of P. denticola and P. pallens were tested by conventional (Fig.…”