How is the quality of the available evidence on molar-incisor hypomineralization treatment? An overview of systematic reviews.

OBJECTIVE: This overview analyzed the quality of the systematic reviews (SRs) available on treatments for molar-incisor hypomineralization (MIH). MATERIAL AND METHODS: Six electronic databases were searched (PubMed/MEDLINE, Scopus, Web of Science, LILACS, Brazilian Bibliography of Dentistry and Cochrane Library) until March 2022. Two reviewers independently performed the selection, the quality assessment (Assessment of Multiple Systematic Reviews 2 - AMSTAR-2), and the risk of bias assessment of the SR (Risk of Bias in Systematic Reviews - ROBIS). RESULTS: Two hundred nine records were retrieved; after removing duplicates and applying the inclusion/exclusion criteria, 5 SRs remained. Three SRs were rated as showing critically low methodological quality and high risk of bias, and two were rated as moderate methodological quality and low risk of bias. The identified treatments that may be suitable for MIH were classified as (1) non-invasive - casein incorporated into toothpaste and sugar-free chewing gum, toothpaste containing arginine, 0.4% stannous fluoride gel; fluoride varnish; (2) micro-invasive - resin sealants for pits and fissures, microabrasion, dental whitening, resin infiltration; (3) invasive - ART restorations, indirect restorations (metal, composite, or ceramic); and (4) mixed intervention - stainless steel crowns. CONCLUSION: Despite the considerable number of published papers included in this set of systematic reviews, the evidence supporting the effectiveness of treatments for treating MIH is limited due to the methodological quality and risk of bias of the systematic reviews, as well as the quality of the primary studies (PROSPERO: CRD42020144831). CLINICAL RELEVANCE: Different treatments have been purposed for MIH treatment, but there is still not enough scientific evidence of good quality for the establishment of a definitive clinical protocol for the treatment of MIH.