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 hig-her 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.