EFFECTS OF NANO-HYDROXYAPATITE DENTIFRICES WITH AND WITHOUT FLUORIDE ON PRIMARY TEETH ENAMEL: A MICRO-CT AND A SEM STUDY

Abstract

Objectives: The ideal remineralization system should provide sufficient ion reserves to provide mineral gain on deeper surfaces, as well as being biocompatible and easy to apply with no adverse effect. The aim of this study was to evaluate the remineralization efficiency of dentifrice form of nanohydroxyapatite alone and its combination with fluoride on initial enamel lesions in primary teeth by micro-CT and SEM. Materials and Methods: The enamel surfaces of 30 extracted primary incisors were treated with nano-hydroxyapatite based (nHAP), nano- hydroxyapatite-fluoride-containing (nHAP+F) and fluoride-containing dentifrice (F), respectively after the pH cycle. Mineral gain and surface properties were evaluated by micro-CT and SEM. Results: nHAP group provided more mineral gain than fluoride containing paste groups but there was no statistically significant difference (p>0.05) according to the micro-CT evaluations. In SEM images, the micropores were completely covered with an apatite layer and mineral precipitations were observed to be wider and more pronounced in the nHAP group. Calcium fluoride crystalline structures exhibited non-homogeneous globular precipitations in the F Group. Conclusions: It was concluded that nHAP dentifrice is as effective as fluoride dentifrice on initial enamel lesions in primary teeth with less cariesresistant enamel surface and therefore it can be safely used.