Remineralization efficiency of dentifrices used for children containing nano-hydroxyapatite and different ingredients: An in vitro evaluation

Aim: The aim of this study is to evaluate remineralization efficiency of nano-hydroxyapatite containing dentifrices comparing to phosphopeptide-amorphous calcium phosphate (CPP-ACP) and fluoride containing dentifrices using scanning electron microscopy (SEM) and energy dispersive spectrometry (SEM/EDX). Methods: 30 extracted primary teeth were used. 3x3 mm2 window areas were created on buccal side of teeth and vertically divided in 3 subgroups for every subject. Middle sections were covered and used as control groups. Artificial caries-like lesions were created and teeth were separated in 3 groups randomly (n=10): group 1; nHA containing dentifrice (Natural toothpaste, Splat, Russia), Group 2; CPP-ACP containing dentifrice (MI Paste ONE, GC, U.S.) and group 3; NaF containing dentifrice (Oral-B Kids, Oral-B, Germany). One more open surface covered before starting pH cycle and teeth were brushed with dentifrices twice daily. Coatings were removed and images were taken under different magnifications by SEM. Elemental spectrums were obtained using SEM/EDX. Statistical analysises were obtained with Mann Whitney U and Kruskal Wallis techniques. Results: P at% and P wt% values were statistically significant for fluoride group in remineralization surfaces comparing to demineralization surfaces (p<0.05). Ca at%, P at% and P wt% values were statistically significant for CPP-ACP group in remineralization surfaces (p<0,05). All remineralization values for each group were similar to those control enamel surfaces. When three groups were compared P at% and P wt% values for fluoride group were higher than nHA and CPP-ACP groups and between nHA and CPP-ACP groups values were statistically insignificant. Conclusion: Remineralization was observed in all groups, remineralization values of fluoride group were higher compared to others. The surface topographic features of the nHA group in the SEM images are closest to the natural enamel, suggesting that this agent can be developed by evaluating it at different concentrations.