# Zirconia-reinforced glass ionomer restorations in molar incisor hypomineralization: a randomized controlled clinical trial

## TL;DR

This study compared zirconia-reinforced and glass-hybrid glass ionomer restorations in children with hypomineralized molars and found both to be equally effective in reducing pain and sensitivity.

## Contribution

The study introduces zirconia-reinforced glass ionomer as a promising restorative material for hypomineralized molars with results comparable to glass-hybrid ionomer.

## Key findings

- Zirconia-reinforced and glass-hybrid glass ionomer showed no significant difference in pain reduction after 12 months.
- Both materials had similar success rates (86.4% vs. 84.1%) in restoring hypomineralized molars.
- Zirconia-reinforced glass ionomer has favorable physical properties and potential for wider pediatric dental applications.

## Abstract

This study aimed to evaluate the effectiveness of zirconia-reinforced glass ionomer (ZrGI), in reducing pain and sensitivity, and to assess its clinical success in comparison to glass-hybrid glass ionomer (GhGI) in hypomineralized permanent first molars (HPFM) following the Atraumatic Restorative Treatment (ART) approach.

This randomized controlled clinical trial included 7–10-year-old children. Eighty-eight HPFMs with evidence of caries, with or without hypersensitivity were included. These molars scored (2a), (2b), (4a), or (4b) according to the MIH Treatment Need Index (MIH-TNI). Selective caries removal was performed using the ART protocol. The test group received ZrGI (Zirconomer®) restorations, and the control group received GhGI (Equia Forte®) restorations. Pain and sensitivity were assessed pre-operatively, using the Visual Analogue Scale (VAS), then re-assessed post-operatively after 1 week and after 3,6,9, and 12 months (M). Clinical success was evaluated, starting from the 3-month visit, using the ART evaluation criteria.

After 12M, the median pain scores for the ZrGI gp., (Q1-Q3; 0.00 – 0.00) and GhGI gp., (Q1-Q3; 0.00 – 0.00) showed no statistically significant difference, (p = 0.329). Median sensitivity scores for the ZrGI gp., (Q1-Q3; 0.00 – 5.00) and the GhGI gp., (Q1-Q3;0.00 – 3.50), also showed no statistically significant difference, (p = 0.344). No significant difference was found between the 12M success rate of ZrGI (86.4%) and GhGI (84.1%), (p = 0.765).

Regarding the reduction of pain and sensitivity, and clinical success, zirconia-reinforced GIC was as effective as glass hybrid GIC in restoring HPFM, using the ART approach.

Zirconia-reinforced glass ionomer cement may be a promising restorative material due to its favorable physical properties and acceptable clinical results, as shown in this study. It may be used as an interim restoration in hypomineralized permanent first molars and holds potential for even wider applications in clinical pediatric dentistry.

Please refer to this study by its ClinicalTrials.gov identifier: NCT05494749

The online version contains supplementary material available at 10.1007/s00784-025-06352-y.