Color change of primary teeth following exposure to an experimentally synthesized liposomal nano-encapsulated ferrous sulfate drop versus the commercially available iron drops

Objectives: This study aimed to assess the color change of primary teeth following exposure to an experimentally synthesized liposomal nano-encapsulated ferrous sulfate drop compared with the commercially iron drops. Materials and methods: In this in-vitro study, liposomal nano-encapsulated ferrous sulfate (lipo-nano-ferr) drop was first synthesized. Next, 110 extracted primary anterior teeth were randomized into two equal groups (sound and demineralized). Each group was randomly divided into 5 subgroups (n = 11) and exposed to Irofant, Feroglobin, Sideral, and lipo-nano-ferr drops for 540 cycles. One subgroup was remained in artificial saliva as the negative control. Tooth color was analyzed before and after the interventions visually, and the rate of iron adsorption was analyzed by atomic absorption spectrometry (AAS), and energy-dispersive X-ray spectroscopy/scanning electron microcopy (EDS/SEM). Data were analyzed using t-test, one-way ANOVA, and LSD test. Results: Iron adsorption was significantly higher by the demineralized specimens than the sound specimens in all subgroups (P < 0.001). A significant difference was noted in iron adsorption among the four subgroups in each of the sound and demineralized groups (P < 0.001). Iron adsorption in the lipo-nano-ferr subgroup was significantly lower than that in Irofant and Feroglobin groups (P < 0.001). The visual inspection results were similar to AAS results. EDS-SEM showed that the atomic percentage of iron in Sideral and lipo-nano-ferr groups was significantly lower than that in Irofant and Feroglobin groups (P < 0.001). Conclusion: Use of nano-encapsulation technology in production of iron drops can significantly decrease the resultant tooth discoloration, causing a clinically negligible color change. © 2021 Japanese Society of Pediatric Dentistr