Autism spectrum disorder and periodontitis risk: A cohort study of 38,203 adolescents

Autistic individuals have worse oral status than neurotypical controls: a systematic review and meta-analysis of observational studies

OBJECTIVE

To compare dental caries, oral hygiene, periodontal status, bruxism, malocclusion, tooth loss, and salivary alterations between autistic and typical developing individuals.

MATERIAL AND METHODS

Observational studies presenting clinical measures of oral outcomes between autism spectrum disorder (ASD) individuals and controls. EMBASE, LILACS, PubMed, PsycINFO, Scopus, Web of Science, Google Scholar, and ProQuest were searched up to June 26, 2023. Pairs of reviewers independently conducted study selection, data extraction, and assessments of methodological quality and certainty of evidence. Meta-analyses of standardized mean differences (SMD) and risk ratio (RR) were performed.

RESULTS

A total of 47 studies comprising 6885 autistic individuals were included in the review. Autistic individuals had significantly higher severity of dental-caries experience in primary teeth (SMD 0.29, 95%CI 0.02, 0.56), of dental plaque presence (SMD 0.59, 95%CI 0.24, 0.94), and of gingivitis (SMD 0.45, 95%CI 0.02, 0.88). Autistic individuals showed higher probability of occurrence of gingivitis (RR 1.34, 95%CI 1.08, 1.66,), bruxism (RR 4.23, 95%CI 2.32, 7.74), overjet (RR 2.16, 95%CI 1.28, 3.64), overbite (RR 1.62, 95%CI 1.02, 2.59), crossbite (RR 1.48, 95%CI 1.02, 2.13), and openbite (RR 2.37, 95%CI 1.46, 3.85), when compared to neurotypical individuals. Most estimates showed a small effect size with very low certainty of evidence.

CONCLUSION

Autistic individuals show worse oral health status than controls.

CLINICAL RELEVANCE

The findings reported herein can help to build health policies to better serve autistic individuals including prevention actions and access to specialized dental care.

Once upon a Time Oral Microbiota: A Cinderella or a Protagonist in Autism Spectrum Disorder?

Autism spectrum disorder (ASD) is a neurodevelopmental disorder evolving over the lifetime of individuals. The oral and gut microbial ecosystems are closely connected to each other and the brain and are potentially involved in neurodevelopmental diseases. This narrative review aims to identify all the available evidence emerging from observational studies focused on the role of the oral microbiome in ASD. A literature search was conducted using PubMed and the Cochrane Library for relevant studies published over the last ten years. Overall, in autistic children, the oral microbiota is marked by the abundance of several microbial species belonging to the Proteobacteria phylum and by the depletion of species belonging to the Bacteroidetes phylum. In mouse models, the oral microbiota is marked by the abundance of the Bacteroidetes phylum. Oral dysbiosis in ASD induces changes in the human metabolome, with the overexpression of metabolites closely related to the pathogenesis of ASD, such as acetate, propionate, and indoles, together with the underexpression of butyrate, confirming the central role of tryptophan metabolism. The analysis of the literature evidences the close relationship between oral dysbiosis and autistic core symptoms; the rebuilding of the oral and gut ecosystems by probiotics may significantly contribute to mitigating the severity of ASD symptoms.