Survival of stainless-steel crowns and composite resin restorations in molars affected by molar-incisor hypomineralization (MIH)

Background Currently, there is no consensus on the superiority of any material for the restorative treatment of molars affected by molar-incisor hypomineralization (MIH). Aim To evaluate the survival of restorations with stainless-steel crown (SSC) or composite resin (CR) in first permanent molars affected by MIH for 24 months. Design In this retrospective cohort study, 61 CR and 54 SSC restorations placed on molars affected by MIH of patients, aged between 7 and 10, that were treated and overseen at a university dental clinic in the period of 2017-2020 were evaluated. The primary outcome was the failure-free survival time. Parametric survival models were used for data censored by interval, and the comparison between SSC and CR was performed using the hazard ratio function with a 95% confidence interval. Results The survival of SSC and CR restorations after 24 months was 94.4% and 49.2%, respectively. This difference was influenced by the presence of previous restoration (aHR = 3.4; 95% CI: 1.2-9.4) and cusp involvement (aHR = 4.0; 95% CI: 1.5-11.2). Conclusion In molars with MIH and the need for restorative treatment, SSC had a significantly higher survival rate than CR over 24 months.