Structural integrity of MIH-affected teeth after treatment with fluoride varnish or resin infiltration: An 18-Month Randomized Clinical Trial.

Costa Nogueira, Vinícius Krieger; Mendes Soares, Igor Paulino; Bullio Fragelli, Camila Maria; Boldieri, Talita; Manton, David John; Bussaneli, Diego Girotto; Loiola Cordeiro, Rita de Cássia

OBJECTIVE To evaluate the influence of fluoride varnish (FV) therapies or resin infiltration (RI) to maintain the structural integrity of Molar Incisor Hypomineralization (MIH) affected teeth. METHODS Fifty-one children aged 6-12 years with at least one incisor and one first permanent molar with yellow/brown MIH opacities were included. Patients were randomly allocated into three groups: FV - Fluoride Varnish (Duraphat); FV + etch - Fluoride Varnish (Duraphat) after enamel etching with 37% phosphoric acid; or RI - Resin Infiltration system (Icon). Opacities were monitored for 18-months. The primary outcome was the loss of integrity due to post-eruptive enamel breakdown (PEB). Covariables included sex, age, DMFT index, opacity colour, plaque, number of MIH-affected teeth and surfaces. Fisher's Exact was used to test the association of treatments with PEB, the Kaplan-Meyer method analysed the survival rates and Cox-regression determined which covariables would predict failure (α = 0.05). RESULTS From a total of 235 teeth, the PEB rate for RI (6.1%) was significantly lower than FV (17.9%; OR 3.0, 95%CI 1.07, 8.48) and FV + etch (17.3%; OR 3.1, 95%CI 1.13, 8.73). DMFT index >3, brown opacities, cusp involvement, and age between 6-8 years predicted PEB (p < 0.05). CONCLUSIONS Resin infiltration positively influenced the structural integrity maintenance of MIH-affected teeth by decreasing the risk of enamel breakdown after18 months follow-up. Registry of Clinical Trials (XXXXX). CLINICAL RELEVANCE Resin infiltration proved to be a more efficacious intervention to maintain the structural integrity of MIH-affected teeth than fluoride varnish therapies.