Glass Ionomer and Composite Survived Equally at One Year in Severe MIH Molars

Edited by Dentaltown staff

High-viscosity glass ionomer cement and resin composite produced statistically similar 12-month restoration survival in molars affected by molar incisor hypomineralization, according to a randomized clinical trial published online Sept. 12 in the Journal of Dentistry.

The trial followed 72 restorations placed in molars with hypomineralization-associated post-eruptive breakdown involving as many as four surfaces. Teeth were randomized to glass ionomer cement or to resin composite placed with an adhesive system.

At 12 months, restoration survival was 91.7% for glass ionomer and 88.9% for resin composite, at P = .690. Survival was assessed against modified atraumatic restorative treatment criteria, with cluster-robust Cox regression and Kaplan-Meier analyses.

The more striking result concerned where the failures came from. A substantial share was attributable not to the restorations themselves but to fresh post-eruptive breakdown in residual hypomineralized enamel adjacent to them, at 30.6% in the glass ionomer group and 25.0% in the composite group, with no significant difference between them at P = .499.

Absolute isolation emerged as an independent predictor across all outcomes in the regression analyses, though the authors characterized that association as exploratory.

Bianca Longo Polo, Giovanna Demarquis Pinto, Ana Clara Amaro Ferdin, Ana Paula Boteon, Heitor Marques Honório, and Daniela Rios conducted the trial at the Bauru School of Dentistry at the University of São Paulo. The São Paulo Research Foundation provided financial support, and GC Corporation supplied the glass ionomer cement used in the study, with no role in design, data collection, analysis, or the decision to publish.

The authors concluded that residual hypomineralized enamel may keep fracturing even when a restoration remains clinically successful, and that management should focus on preserving the tooth as a whole rather than on restoration integrity alone. Follow-up ran 12 months, so longer-term behavior of either material in these teeth remains open.

Sources:
Journal of Dentistry, “Tooth-level outcomes in molar incisor hypomineralisation affected molars with post-eruptive breakdown: a randomized clinical trial comparing glass ionomer and resin composite,” published online Sept. 12, 2026: doi.org/10.1016/j.jdent.2026.107044
PubMed record, PMID 42731776: pubmed.ncbi.nlm.nih.gov/42731776