Abstract An increasing number of systematic reviews (SR) has investigated the association between dental caries and nutritional status in children and adolescents, thus requiring an overview to compile the information in a single piece of evidence. Therefore, this study aimed to evaluate and summarize evidence from published SR on the association between dental caries and nutritional status in children and adolescents. A wide search was conducted on May 29, 2023, in six databases (Medline via PubMed, Scopus, Web of Science, Cochrane library, Embase, and the Virtual Health Library – VHL). An additional search was performed in the gray literature (Open grey and Google Scholar), SR registration databases, and the list of references of the included SR. Our inclusion criteria were based on acronym PECOS. Overall, two reviewers independently extracted the data, evaluated the risk of bias (ROBIS), and assessed the quality of the chosen studies (AMSTAR-2). Data from the included meta-analysis were summarized and certainty of evidence using the GRADE approach was performed. After removing duplicates and applying our eligibility criteria, 19 SR from 2006-2022 were included. We found that 17 SR showed high risk of bias and critically low methodological quality. We observed an association between dental caries experiences and nutritional status since seven SR found an association between obesity/overweight and dental caries; one, an association between underweight and dental caries; and eleven, no associations. The meta-analysis showed divergent results according to the study designs, used indices, and participants’ age group, and were scored as having a very low certainty of evidence. Therefore, based on the high risk of bias, low methodological quality, and very low certainty of evidence of the chosen SR, most studies found no association between children and adolescents’ nutritional status and dental caries experience.

Resumo Atualmente as investigações têm focado na identificação de Polimorfismos de Núcleo Único (SNP) envolvidos na resposta do hospedeiro e sua capacidade de gerar uma deficiência de imunidade. O objetivo deste estudo foi realizar uma revisão sistemática (RS) e uma meta-análise para avaliar a associação entre o polimorfismo do gene TNF-α (-308 G> A) e os fenótipos de periodontite apical (PA). Esta RS foi registrada na base de dados PROSPERO, CRD42016035688, e foi conduzida seguindo o método PRISMA. Foi realizada uma ampla pesquisa de estudos. Foram utilizadas as seguintes bases de dados: PubMed, Scopus, Web of Science e BVS (Medline, SciELO, Ibecs e Lilacs). Foram utilizados os seguintes descritores (MeSH) “Periapical Periodontitis,” “Periapical Abscess,” “Polymorphism, Genetic,” and “Polymorphism, Single Nucleotide”. Sinônimos, termos relacionados e termos livres foram incluídos. Foram selecionadas investigações clínicas de indivíduos com diferentes fenótipos de PA em dentes permanentes. Após a aplicação dos critérios de elegibilidade, os estudos selecionados foram classificados através da avaliação da qualidade metodológica. Foi utilizado um modelo de efeito fixo para a metanálise. A pesquisa inicial identificou 71 referências. Após a exclusão de resumos duplicados, 33 foram selecionados. Destes, dois eram elegíveis para a avaliação da qualidade e foram classificados como sendo de evidência moderada. Os estudos incluídos não demonstraram associação entre PA e o TNF-α-308 G>A. No entanto, a metanálise demonstrou associação entre a distribuição do genótipo e os fenótipos da PA (OR = 0,49, intervalo de confiança=0,25, 0,96; p=0,04). O papel do TNF-α-308 G>A em fenótipos da PA é discutível. São necessários mais estudos para confirmar e compreender os mecanismos subjacentes à associação identificada.

Abstract Currently, investigations have focused on the identification of Single Nucleotide Polymorphisms (SNP) involved in host response and its ability to generate an immunity deficiency. The aim of this study was to perform a systematic review (SR) and meta-analysis to evaluate the association between TNF-α -308 G>A polymorphism and apical periodontitis (AP) phenotypes. A broad search for studies was conducted. The following databases were used: PubMed, Scopus, Web of Science, and VHL (Medline, SciELO, Ibecs, and Lilacs). The MeSH terms “Periapical Periodontitis,” “Periapical Abscess,” “Polymorphism, Genetic,” and “Polymorphism, Single Nucleotide” were used. MeSH synonyms, related terms, and free terms were included. Clinical investigations of individuals with different AP phenotypes in permanent teeth were selected. After application of the eligibility criteria, selected studies were qualified by assessing their methodological quality. A fixed effect model was used for the meta-analysis. The initial search identified 71 references. After excluding duplicate abstracts, 33 were selected. From these, two were eligible for quality assessment and were classified as being of moderate evidence. The included studies did not demonstrate association between AP and TNF-α -308 G>A SNP. However, the meta-analysis demonstrated an association between the genotype distribution and AP phenotype (OR= 0.49; confidence interval= 0.25, 0.96; p=0.04). The role of TNF-α -308 G>A SNP in AP phenotypes is debatable. Further studies are needed to confirm and understand the underlying mechanisms of the identified association.