Supragingival Plaque Microbial Community Analysis of Children with Halitosis

Abstract

As one of the most complex human-associated microbial habitats, the oral cavity harbors hundreds of bacteria. Halitosis is a prevalent oral condition that is typically caused by bacteria. The aim of this study was to analyze the microbial communities and predict functional profiles in supragingival plaque from healthy individuals and those with halitosis. Ten preschool children were enrolled in this study; five with halitosis and five without. Supragingival plaque was isolated from each participant and 16S rRNA gene pyrosequencing was used to identify the microbes present. Samples were primarily composed of Actinobacteria, Bacteroidetes, Proteobacteria, Firmicutes, Fusobacteria, and Candidate phylum TM7. The α and β diversity indices did not differ between healthy and halitosis subjects. Fifteen operational taxonomic units (OTUs) were identified with significantly different relative abundances between healthy and halitosis plaques, and included the phylotypes of sp., sp., sp., sp., sp.,, and . We suggest that these OTUs are candidate halitosis-associated pathogens. Functional profiles were predicted using PICRUSt, and nine level-3 KEGG Orthology groups were significantly different. Hub modules of co-occurrence networks implied that microbes in halitosis dental plaque were more highly conserved than microbes of healthy individuals' plaque. Collectively, our data provide a background for the oral microbiota associated with halitosis from supragingival plaque, and help explain the etiology of halitosis.

Leptotrichia species in human infections II

“…L. hofstadii has been isolated from subgingival samples and gingival crevicular fluid of periodontitis patients [83], saliva, biofilm from caries [49,65], the mucosal surface of patients with removable partial dentures, and root canals of patients with or without disease [34,56,84], tumor tissue [40], and tongue coatings of halitosis patients (Table 2) [81,82]. …”

“…Leptotrichia species were also isolated from bronchoalveolar lavage fluid, and patients with leukocytosis, hypoxemia, and dyspnea [24]. Further, Leptotrichia species were recovered from healthy patients with oral cancer, premalignant oral lesion [18,28,33,56,91], edentulous infants [29], human vaginal fluid of sexually active and inactive individuals [30,32], HIV-seropositive and -seronegative patients [46], pancreatic cancer patients [18,66], black pigmented stain caries patients [63], and patients with halitosis (Table 2) [42,65,81,82]. Besides, Leptotrichia species were isolated from the blood [4,5,22,74], the amniotic fluid of a patient with a wound and respiratory difficulties [4], breast milk of obese women with gestational diabetes and normal weight [36], oral samples of a patient with new-onset rheumatoid arthritis [20], oral lichen planus patients [88], and even from fermenting Lees liquor [39].…”

“…Leptotrichi a has also been associated with halitosis (oral malodor) [42,65,81,82]. Most of the species within the core microbiome of the tongue-coating biofilm are Gram-negative anaerobic bacteria that are adaptable to the tongue-coating environment (Table 2) [81].…”

Induction and inhibition of oral malodor

“…Recently, a molecular approach based on the 16S rRNA gene, which is independent of microbial cultivation, has been employed to investigate the diversity of oral microbiota associated with oral malodor (Haraszthy et al, ; Kazor et al, ; Ren, Xun, et al, ; Ren, Zhang, et al, ; Riggio et al, ; Seerangaiyan, Winkelhoff, Harmsen, Rossen, & Winkel, ; Takeshita et al, , ; Yang et al, ). Specifically, 16S rRNA pyrosequencing analyses, which are currently the most accurate method of identifying microbiota, have provided information on microbiota of the saliva, tongue, and plaque associated with oral malodor (Ren, Xun, et al, ; Ren, Zhang, et al, ; Seerangaiyan et al, ; Takeshita et al, ; Yang et al, ). A study that identified the tongue microbiota of 29 adult volunteers found that the structure of the microbiota was relatively stable within each individual, and its variation was correlated with changes in the H 2 S level (Yang et al, ).…”

“…Table shows the distribution of bacterial taxa that were characteristically more predominant in the high H 2 S and CH 3 SH groups. Ren, Xun, et al ()) and Ren, Zhang, et al ()) examined the microbial composition of the tongue coating, saliva, and supragingival plaque of children with oral malodor compared to healthy controls. Study subjects were 4–5 years old and the microbiota of the tongue coating and saliva from 10 subjects with oral malodor and 10 subjects with no odor were compared (Ren, Xun, et al, ).…”