In vivo Experimental Study on the Influence of Sodium Fluoride and Amoxicillin/Clavulanic Acid on the Minerals Composition of Dental Enamel

The aim of this study was to assess the morphological and chemical composition changes induced by the chronic intake of sodium fluoride (NaF) and Amoxicillin in mice enamel. 35 C57BL/6 adult male mice, were randomly divided into a control and 4 treatment groups (n = 7). After acclimatization, the experimental groups were simultaneously treated with 25 ppm (group 2 and 3) and 50ppm (group 4 and 5) of NaF, and 50mg/kg BW (group 2 and 4) and 100 mg/kg BW (group 3 and 5) of Amoxicillin as Amoxicillin/clavulanic acid (AMC). NaF was supplied through drinking water without restricting access, and AMC administered through subcutaneous injection, once per day, for 60 days. After harvesting, lower incisors’ enamel was subjected to a scanning electron microscope (SEM) and to an energy dispersive X-ray analysis (EDX). In the treatment groups, SEM and EDX analysis in treatment groups showed an increasing trend of weight percentage (wt%) for C, N, O, F, Na and C/O, F/Fe ratio, and also a decreasing trend of wt% for P, Cl, Ca, Fe and Ca/P ratio. Morphological changes ranged from fissures and short grooves with pits-like appearance, in group 2 sometimes associated with limited demineralized areas looking like irregular scratches, up to demineralized areas extended in the outer enamel, which in group 5 gives the enamel the corroded look. The severity of the morphological changes in the mice enamel varied with the supplied dose of NaF and AMC, and had a uniform pattern in each experimental group. SEM analysis revealed a hypoplasia on the outer enamel and EDX analysis showed a hypomineralisation at the level of the outer enamel.