Effects of Fluoride Treatment on Enamel of Primary Teeth: A Pilot Study Using Micro-x-ray Diffractometry

Abstract

Aim: The purpose of this study was to investigate the effect of fluoride treatment on the natural surface of enamel using micro-x-ray diffractometry (XRD). Materials and Methods: Two enamel fragments (around 1mm^3) were cut from the sound area of two primary incisors. The fragments were mounted on two XRD three-D holders using sticky wax and the XRD diffraction patterns were then recorded, respectively. The XRD analysis was carried out using micro-x-ray diffractometer system (D8 Gadds Hi-star Area Detector, Bruker) The value of a-axis and c-axis were calculated using the Bragg's equation 2dsinθ=λ from the (300) and (002) reflections respectively. The natural surface of the enamel fragments were then subjected to 2% NaF gel treatment for 4 minutes. After the fluoride treatment, the sample and the sample holder were put back to the same position as that of the before treatment measurement and the XRD patterns were recorded again. Results: No new phase can be detected from the diffraction pattern of any sample. The a-axis parameters for the two enamel fragments were 9.481 and 9.470 A, while the c-axis parameters were 6.880 to 6.883 A. After the fluoride treatment, no change was found in the a- and c- axes and the intensity of all the reflection peaks. Conclusion: The four minutes' 2% NaF gel treatment did not cause the crystallinity change in enamel, which was detectable by using Micro-XRD. This indicated that the micro-x-ray diffractometry might not be sensitive enough to detect the minor fluoride changes in the treated samples.