Longitudinal assessment of enamel wear in MIH-Affected molars and the effect of diode laser therapy using 3D intraoral scanning: A 24-month pilot study

Objectives: This pilot study evaluates the feasibility and accuracy of using 3D intraoral scanning combined with digital superimposition techniques to monitor enamel wear progression in first permanent molars affected by molar-incisor hypomineralization (MIH) over 24 months. A secondary objective was to preliminarily evaluate the protective effects of adjunctive diode laser therapy on enamel preservation. Methods: Six pediatric patients (aged 6–10 years) with mild to moderate MIH were enrolled. Each child contributed one MIH-affected molar and one contraletaral unaffected molar for analysis. Intraoral scans were performed at baseline (T0), 8 months (T1), and 24 months (T2). Follow-ups scans digitally superimposed onto baseline models using metrology-grade software (Geomagic Control X). Enamel wear was quantified using root mean square (RMS) deviation and maximum vertical tissue loss (mean, SD; μm) at predefined occlusal landmarks. MIH-affected molars received diode laser treatment at both T0 and T1. Group comparisons were performed using Mann–Whitney U tests. Results: The digital workflow enabled high-precision, longitudinal monitoring of enamel surface loss. Laser-treated MIH teeth exhibited lower mean wear than untreated controls at both follow-up intervals (T1–T0: 29.9 μm vs. 33.7 μm; T2–T0: 43.8 μm vs. 51.4 μm), although these differences were not statistically significant (p > 0.05). Color-coded deviation maps effectively illustrated localized pattens of enamel loss. Conclusion: The proposed digital workflow is both feasible and reliable for tracking enamel loss in MIH-affected molars over time. Diode laser treatment showed a tendency toward reduced wear, though larger studies are needed. These findings support the integration of digital analysis tools into pediatric MIH management and preventive care. Clinical implications: MIH is associated with accelerated enamel breakdown in children. Although 3D intraoral scanning enables precise, non-invasive monitoring, its use in MIH cases is still limited. Moreover, the clinical efficacy of diode laser therapy for enhancing enamel resistance requires further investigation.