Salivary Microbiological and Gingival Health Status Evaluation of Adolescents With Overweight and Obesity: A Cluster Analysis

Overweight/obesity and dental caries in Brazilian children and adolescents: a systematic review and meta-analysis

This review aimed to assess the association between overweight/obesity and dental caries in Brazilian children/adolescents. Searches were performed in the Web of Science, Scopus, Cochrane, PubMed, Embase and SciELO, Lilacs and Open Grey literature databases up to June 2022. The Joanna Briggs Institute checklist for analytical cross-sectional studies, the checklist for cohort studies, and the checklist for case-control studies were used. A total of 41 publications were included, and 15 meta-analyses were performed. The authors analyzed the differences in weighted mean difference (MD) and odds ratios (OR), and their corresponding confidence intervals (CI) (95%) for dental caries among eutrophic and obese and/or overweight children/adolescents. Meta-analyses showed that there was no association between overweight and/or obesity and dental caries in Brazilian children/adolescents for most anthropometric reference curves using BMI (Body Mass Index). A greater experience of dental caries was associated with well-nourished adolescents in permanent dentition, compared with obese individuals in the same dentition, as classified by the CDC 2000 curve (OR = 2.53, 95% CI;1.49-4.29; p = 0.0006; I2 = 0%) in dichotomous outcome studies, and (MD = 0.61, 95%CI: 0.08-1.15; p = 0.02; I2 = 0%) in continuous studies. The strength of the evidence of the results was classified as very low, low or moderate. It was concluded that there is no association between overweight and/or obesity and dental caries in Brazilian children/adolescents for most anthropometric reference curves using BMI. A greater experience of dental caries was associated with well-nourished adolescents in permanent dentition, compared with obese individuals in the same dentition, as classified by the CDC 2000 curve.

Salivary and gingival crevicular fluid biomarkers of periodontal health and/or obesity among children and adolescents: A systematic review and meta-analysis

Objectives

To investigate the association of salivary and gingival crevicular fluid (GCF) biomarkers with periodontal status and obesity in children and adolescents.

Data/sources

A literature search up to July 2023 was conducted through PubMed, Web of Science, Embase, ProQuest Medical Database, ProQuest SciTech Premium Collection, and the Cochrane Library. Observational studies comparing salivary and GCF biomarkers in children and adolescents with compromised periodontal status and/or obesity were included for data extraction. A meta-analysis was performed to estimate the overall standardised mean difference.

Study selection

Fifteen observational studies met the inclusion criteria and were included in this systematic review. Meta-analysis was only applicable in synthesising the dyadic relationship between GCF biomarkers and obesity. The results demonstrated that children and adolescents with obesity had significantly higher GCF levels of tumour necrosis factor-alpha (SMD:0.56; 95% CI:0.07, 1.04), adiponectin (SMD:0.33; 95% CI:0.06, 0.60), leptin (SMD:0.52; 95% CI:0.15, 0.90), and interleukin-1 beta (SMD:0.71; 95% CI:0.44, 0.99) than those with normal weight.

Conclusion

To date, no study has well addressed the triadic association between salivary or GCF biomarkers, periodontal status, and obesity among children and adolescents. Further in-depth, high-quality studies are required to investigate these associations.

Clinical significance

Periodontal disease and obesity are growing public health crises worldwide. Their relationship has been intensively studied. Investigating the salivary or GCF biomarkers alterations could help better understand the relationship between periodontal disease and obesity, which would assist in tailoring future oral health promotion programs.

Bypass gastroplasty impacts oral health, salivary inflammatory biomarkers, and microbiota: a controlled study

OBJECTIVES

Knowledge about the impact of gastroplasty on oral health and salivary biomarkers is limited. The aim was to prospectively evaluate oral health status, salivary inflammatory markers, and microbiota in patients undergoing gastroplasty compared with a control group undergoing a dietary program.

MATERIALS AND METHODS

Forty participants with obesity class II/III were included (20 individuals in each sex-matched group; 23-44 years). Dental status, salivary flow, buffering capacity, inflammatory cytokines, and uric acid were assessed. Salivary microbiological analysis (16S-rRNA sequencing) assessed the abundance of genus, species, and alpha diversity. Cluster analysis and mixed-model ANOVA were applied.

RESULTS

Oral health status, waist-to-hip ratio, and salivary alpha diversity were associated at baseline. A subtle improvement in food consumption markers was observed, although caries activity increased in both groups, and the gastroplasty group showed worse periodontal status after three months. IFNγ and IL10 levels decreased in the gastroplasty group at 3 months, while a decrease was observed in the control group at 6 months; IL6 decreased in both groups (p < 0.001). Salivary flow and buffering capacity did not change. Significant changes in Prevotella nigrescens and Porphyromonas endodontalis abundance were observed in both groups, while alpha diversity (Sobs, Chao1, Ace, Shannon, and Simpson) increased in the gastroplasty group.

CONCLUSIONS

Both interventions changed in different degrees the salivary inflammatory biomarkers and microbiota, but did not improve the periodontal status after 6 months.

CLINICAL RELEVANCE

Although the observed discrete improvement in dietary habits, caries activity increased with no clinical improvement in the periodontal status, emphasizing the need of oral health monitoring during obesity treatment.

Characterization of the oral and gut microbiome in children with obesity aged 3 to 5 years

The ever-increasing global prevalence of obesity has trended towards a younger age. The ecological characteristics and changes of the oral and gut microbial community during childhood are poorly understood.In this study, we analyzed the salivary and fecal microbiota of 30 children with obesity and 30 normal weight children aged 3-5 years via third-generation long-range DNA sequencing,with the aim of understanding the structure of childhood microbiota and identifying specific oral and gut microbial lineages and genera in children that may be associated with obesity.The results revealed significant variation in alpha diversity indices among the four groups (Chao1: P &lt; 0.001; observed species: P &lt; 0.001; Shannon &lt; 0.001). Principal coordinate analysis (PCoA) and nonmetric multidimensional scaling (NMDS) revealed significant differences in oral and gut microbial community structure between obesity and controls. The Firmicutes/Bacteroidetes (F/B) abundance ratios of oral and intestinal flora among children with obesity were higher than those of controls. The most abundant phyla and genera found in oral and intestinal flora were Firmicutes, Proteobacteria, Bacteroidetes, Neisseria, Bacteroides, Faecalibacterium, Streptococcus, Prevotella and so on. Linear discriminant analysis effect size (LEfSe) revealed higher proportions of Filifactor (LDA= 3.98; P &lt; 0.05) and Butyrivibrio (LDA = 2.54; P &lt; 0.001) in the oral microbiota of children with obesity, while the fecal microbiota of children with obesity were more enriched with Faecalibacterium (LDA = 5.02; P &lt; 0.001), Tyzzerella (LDA=3.25; P &lt; 0.01), Klebsiella (LDA = 4.31; P &lt; 0.05),which could be considered as dominant bacterial biomarkers for obesity groups.A total of 148 functional bacterial pathways were found to significantly differ in the oral and gut microbiota among controls and obesity using PICRUSt 2. Most predicted functional pathways were clustered in biosynthesis. In conclusion, This work suggests there were significant differences in oral and gut microbiota in controls and obesity groups, microbiota dysbiosis in childhood might have significant effect on the development of obesity.

Role of oral and gut microbiota in childhood obesity

Childhood obesity not only causes damage to children's respiratory, cardiovascular, endocrine, motor, and other systems but also is a significant risk factor for metabolic diseases such as obesity in adulthood, which has become one of the serious public health problems worldwide. The etiology and pathogenesis of obesity are complex. In addition to genetic and lifestyle factors, recent studies have found that the microbes in the digestive tract play a crucial role in the occurrence and development of obesity. Among them, the gut microbiota has been confirmed to be one of the important pathogenic factors of obesity, which can mediate the occurrence and development of obesity by interfering with the balance of host energy metabolism and inducing low-grade chronic inflammation throughout the host. Targeting the gut microbiota to treat obesity through various methods such as fecal microbiota transplantation, dietary intervention, and probiotic supplementation has become a research hotspot in obesity treatment. In addition, the oral microbiota is also considered closely related to the occurrence and development of obesity due to its regulatory effect on the balance of gut microbiota. Exploring the relationship between oral and gut microbiota and childhood obesity elucidates the pathogenesis and treatment concepts of childhood obesity from a new perspective. It may provide new methods for the prevention and treatment of childhood obesity in the future.

Is oral microbiota associated with overweight and obesity in children and adolescents? A systematic review

This article aims to verify the relationship between the composition and diversity of oral microbiota with overweight and obese children and adolescents. This systematic review was registered in PROSPERO, followed PRISMA 2020, and included an electronic search until March 2022, in PubMed/MEDLINE, Web of Science, Scopus, and The Cochrane Library databases. Studies were eligible if they compared the oral microbiota according to nutrition status among children and adolescents. Independent peers using JBI Critical Appraisal Checklists assessed the quality of studies. Eleven studies were eligible to be included in this review, with a total of 1,695 children and adolescents, 224 were obese, 190 were overweight, 1,154 were eutrophics and 127 were underweight. The most frequent phyla in overweight and obese children and adolescents, in comparison to their counterparts were Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria and Fusobacteria. It was identified that nine of the eleven articles selected showed an association between oral microbiota and overweight and obesity in children and adolescents. We observed that there is an important association between oral bacterial composition diversity and overweight and obesity. This finding indicates the relevance of the evaluation and surveillance in oral health to control cases of overweight and obesity in children and adolescents.

Metagenomic analysis reveals associations between salivary microbiota and body composition in early childhood

Several studies have shown that body mass index is strongly associated with differences in gut microbiota, but the relationship between body weight and oral microbiota is less clear especially in young children. We aimed to evaluate if there is an association between child growth and the saliva microbiome. We hypothesized that associations between growth and the saliva microbiome would be moderate, similarly to the association between growth and the gut microbiome. For 236 toddlers participating in the New Hampshire Birth Cohort Study, we characterized the association between multiple longitudinal anthropometric measures of body height, body weight and body mass. Body Mass Index (BMI) z-scores were calculated, and dual-energy x-ray absorptiometry (DXA) was used to estimate body composition. Shotgun metagenomic sequencing of saliva samples was performed to taxonomically and functionally profile the oral microbiome. We found that within-sample diversity was inversely related to body mass measurements while community composition was not associated. Although the magnitude of associations were small, some taxa were consistently associated with growth and modified by sex. Certain taxa were associated with decreased weight or growth (including Actinomyces odontolyticus and Prevotella melaninogenica) or increased growth (such as Streptococcus mitis and Corynebacterium matruchotii) across anthropometric measures. Further exploration of the functional significance of this relationship will enhance our understanding of the intersection between weight gain, microbiota, and energy metabolism and the potential role of these relationships on the onset of obesity-associated diseases in later life.

Obesity influences composition of salivary and fecal microbiota and impacts the interactions between bacterial taxa

Obesity is an increasing global health concern and is associated with a broad range of morbidities. The gut microbiota are increasingly recognized as important contributors to obesity and cardiometabolic health. This study aimed to characterize oral and gut microbial communities, and evaluate host: microbiota interactions between clinical obesity classifications. We performed 16S rRNA sequencing on fecal and salivary samples, global metabolomics profiling on plasma and stool samples, and dietary profiling in 135 healthy individuals. We grouped individuals by obesity status, based on body mass index (BMI), including lean (BMI 18-124.9), overweight (BMI 25-29.9), or obese (BMI ≥30). We analyzed differences in microbiome composition, community inter-relationships, and predicted microbial function by obesity status. We found that salivary bacterial communities of lean and obese individuals were compositionally and phylogenetically distinct. An increase in obesity status was positively associated with strong correlations between bacterial taxa, particularly with bacterial groups implicated in metabolic disorders including Fretibacterium, and Tannerella. Consumption of sweeteners, especially xylitol, significantly influenced compositional and phylogenetic diversities of salivary and fecal bacterial communities. In addition, obesity groups exhibited differences in predicted bacterial metabolic activity, which was correlated with host's metabolite concentrations. Overall, obesity was associated with distinct changes in bacterial community dynamics, particularly in saliva. Consideration of microbiome community structure and inclusion of salivary samples may improve our ability to understand pathways linking microbiota to obesity and cardiometabolic disease.

Interplay Among the Oral Microbiome, Oral Cavity Conditions, the Host Immune Response, Diabetes Mellitus, and Its Associated-Risk Factors-An Overview

This comprehensive review of the literature aimed to investigate the interplay between the oral microbiome, oral cavity conditions, and host immune response in Diabetes mellitus (DM). Moreover, this review also aimed to investigate how DM related risk factors, such as advanced age, hyperglycemia, hyperlipidemia, obesity, hypertension and polycystic ovary syndrome (PCOS), act in promoting or modifying specific mechanisms that could potentially perpetuate both altered systemic and oral conditions. We found that poorly controlled glycemic index may exert a negative effect on the immune system of affected individuals, leading to a deficient immune response or to an exacerbation of the inflammatory response exacerbating DM-related complications. Hyperglycemia induces alterations in the oral microbiome since poor glycemic control is associated with increased levels and frequencies of periodontal pathogens in the subgingival biofilm of individuals with DM. A bidirectional relationship between periodontal diseases and DM has been suggested: DM patients may have an exaggerated inflammatory response, poor repair and bone resorption that aggravates periodontal disease whereas the increased levels of systemic pro-inflammatory mediators found in individuals affected with periodontal disease exacerbates insulin resistance. SARS-CoV-2 infection may represent an aggravating factor for individuals with DM. Individuals with DM tend to have low salivary flow and a high prevalence of xerostomia, but the association between prevalence/experience of dental caries and DM is still unclear. DM has also been associated to the development of lesions in the oral mucosa, especially potentially malignant ones and those associated with fungal infections. Obesity plays an important role in the induction and progression of DM. Co-affected obese and DM individuals tend to present worse oral health conditions. A decrease in HDL and, an increase in triglycerides bloodstream levels seem to be associated with an increase on the load of periodontopathogens on oral cavity. Moreover, DM may increase the likelihood of halitosis. Prevalence of impaired taste perception and impaired smell recognition tend to be greater in DM patients. An important interplay among oral cavity microbiome, DM, obesity and hypertension has been proposed as the reduction of nitrate into nitrite, in addition to contribute to lowering of blood pressure, reduces oxidative stress and increases insulin secretion, being these effects desirable for the control of obesity and DM. Women with PCOS tend to present a distinct oral microbial composition and an elevated systemic response to selective members of this microbial community, but the association between oral microbiome, PCOS are DM is still unknown. The results of the studies presented in this review suggest the interplay among the oral microbiome, oral cavity conditions, host immune response and DM and some of the DM associated risk factors exist. DM individuals need to be encouraged and motivated for an adequate oral health care. In addition, these results show the importance of adopting multidisciplinary management of DM and of strengthening physicians-dentists relationship focusing on both systemic and on oral cavity conditions of DM patients.

Salivary Microbiome Diversity in Kuwaiti Adolescents with Varied Body Mass Index-A Pilot Study

The potential role of the salivary microbiome in human diseases has increasingly been explored. The salivary microbiome has been characterized in several global populations, except the Arabian Gulf region. Hence, in this pilot study, we profiled the salivary microbiome of Kuwaiti adolescents with varied body mass indexes (BMI). The analyses of core microbiome composition showed Firmicutes, Bacteroidota, Proteobacteria, Patescibacteria, Fusobacteriota, Actinobacteriota, and Campylobacterota as the common phylum found in the Kuwaiti adolescent population. We also illustrated a diverse microbial community among the sampled individuals grouped according to their BMI. Notably, the overweight group was found with a higher number of distinct taxa than other groups. As such, the core microbiome composition was found to be significantly different (p-value < 0.001) across different BMI groups. Overall, this pilot investigation outlined the microbial diversity and suggested that changes in salivary microbiome composition in people with obese or overweight BMI might reflect their susceptibility to oral diseases.

Observational Study Regarding the Relationship between Nutritional Status, Dental Caries, Mutans Streptococci, and Lactobacillus Bacterial Colonies

The prevalence of dental caries and obesity is high as both raise significant health problems. The objective of this study was to evaluate the relationship between dental caries, the number of salivary colonies forming units of Mutans Streptococci (MS) and Lactobacillus (LB), and the nutritional status in a group of children from Transylvania. This observational study used a sample of 154 school children, aged 9 to 12 years. The prevalence of caries was measured using the decayed, missing, and filled teeth index for deciduous teeth (dmft index) and for permanent teeth (DMFT index). Height and weight were assessed for each subject, and their body mass index (BMI) percentile was calculated. Salivary levels of Mutans Streptococci (MS) and Lactobacillus (LB) were determined using the CRT Bacteria Test from Ivoclar Vivadent. In our study, we found a positive association between the BMI percentile, MS count, LB count, tooth brushing frequency, and the incidence of dental caries in children aged 9 to 12 years old. Future preventive programs should include nutrition control in order to prevent both the apparition of dental caries and obesity in children.