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Author Spotlight: Establishing an Accurate Microhardness Testing Protocol for Craniofacial Tissues
Published on: April 26, 2024
Assessment of Remineralization Treatment on Primary Enamel's Microhardness and Mineral Composition Post Iron Drop
Aneseh Sadat Tabatabaei Rad1, Sara Tavassoli-Hojjati2, Reyhane Sadat Hoda2
1Dental Research Center, Restorative Department, School of dentistry, Shahid Beheshti University of Medical Science, Tehran, Iran, sbmu.ac.ir.
Objectives:
This study assessed the effects of remineralizing agents on microhardness and mineral content of primary enamel following iron drop exposure.
Materials And Methods:
In this in vitro study, 36 sound primary anterior teeth were randomly assigned to four groups (n = 9) of (I) casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), (II) fluoride varnish, (III) MI varnish, and (IV) control. The microhardness of specimens was initially measured by a Vickers hardness tester. The specimens were immersed in iron drop solution in a shaker incubator at 37°C for 5 min. They were then rinsed with distilled water, and their microhardness was measured again. The teeth were subsequently split in half. The buccal halves were exposed to the remineralizing agents for 4 h, rinsed with distilled water, and immersed in artificial saliva for 24 h. They were then immersed in a demineralizing solution for 6 h, followed by a remineralizing solution for 18 h at 37°C for 10 days. The final microhardness was measured again. The buccal and lingual halves underwent energy dispersive X-ray spectroscopy for mineral content analysis. Data were analyzed by one-way ANOVA and Tukey test (α = 0.05).
Results:
Iron drop exposure significantly decreased, and remineralizing agents significantly increased the microhardness (both p < 0.001). The three remineralizing agents had no significant difference in enhancement of microhardness (p = 0.493). The four groups had significant differences in Ca, F, and Fe contents after the intervention (p < 0.05).
Conclusion:
Iron drop exposure decreased, and remineralizing agents increased the microhardness and mineral content of primary enamel under in vitro conditions.

