Efficacy of Remineralizing Agents for Prevention of Microhardness Reduction and Change in Mineral Content of Enamel in Anterior Primary Teeth after Exposure to Iron Drop.

Background: Some alterations in the enamel structure of primary teeth have been reported following iron drop consumption. The efficacy of different remineralizing agents for this problem is still challenging.

Purpose: This study aimed to assess the efficacy of remineralizing agents for prevention of microhardness reduction and change in primary enamel mineral content after exposure to iron drop.

Materials and method: In this experimental study, 36 sound primary anterior teeth were assigned to four groups of control, casein phosphopeptide amorphous calcium phosphate (CPP-ACP), fluoride varnish (FV), and CPP-ACP+FV (MI varnish). The baseline microhardness of the teeth was first measured by Vickers hardness tester using 50 g load for 10 seconds. Next, the microhardness was measured after remineralizing agents were applied on the specimens. After the application of iron drop for 5 minutes, and pH cycling for 10 days, the final microhardness of specimens was registered. Specimens were also subjected to energy dispersive X-ray spectroscopy (EDS) in the control group, after remineralization and after the application of iron drop. Data were analyzed by one-way ANOVA, Tukey's test, and Tamhane's test.

Results: The final microhardness was significantly higher in all remineralized groups compared to the control group (p Value= 0.003). The final microhardness was significantly higher in MI varnish compared to FV (p= 0.027), CPP-ACP (p= 0.03), and control (p< 0.0001) groups. According to EDS, calcium (Ca) and ferric (Fe) content were significantly different between the remineralizing groups and control groups in the final step (p< 0.00001).

Conclusion: Application of CPP-ACP, FV, and MI varnish prior to iron drop exposure can improve microhardness. MI varnish had significantly higher efficacy for this purpose than the other two remineralizing agents.