Experimental study of microhardness of glass ionomer cements and E-max MT ceramics compared to primary tooth enamel

Background. The study of microhardness of dental materials, especially those used in pediatric dentistry, is an important task in modern dentistry. Glass ionomer cements (GICs) and E-max MT ceramics are widely used for tooth restoration, but their mechanical properties compared to primary tooth enamel remain understudied.

Objective. To evaluate the microhardness of glass ionomer cements (Fuji-9, Vitremer) and E-max MT ceramics in comparison with primary tooth enamel.

Materials and methods. Laboratory tests were performed on 25 samples of each material.

Microhardness was measured using a manual digital press RPG-75. Statistical analysis included Shapiro – Wilk, Levene, Bartlett, Kruskal-Wallis, and Dunn tests (p < 0.05).

Results. Primary tooth enamel exhibited microhardness of 1.97 ± 0.22 kN, surpassing GICs (Fuji-9: 1.11 ± 0.15 kN; Vitremer: 1.36 ± 0.07 kN) but remaining inferior to E-max MT ceramics (8.03 ± 0.71 kN). Intergroup differences were statistically significant (p < 0.05).

Conclusion. E-max MT ceramics show the highest strength, making them suitable for load-bearing restorations. GICs, while less durable than natural enamel, offer advantages in biocompatibility and anti-caries effects, which are critical in pediatric dentistry.

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