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Abstrak :
Flouride intrusion into enamel surface is one of the important factors of success in topical flouridation. Objective: to compare EDX and flourescence measurement methods of flouride intrusion into enamel surface after anchovy application. Methods: 5 extracted impacted third molars were immersed in sterile saline solution for 24 hours. The buccal surfaces of the teeth were painted with nail varnish, and a window of 5 mm2 at the center of each surface was left unpainted. Dried anchovies from the market were heated and powdered, and 5 g of this anchovy powder was diluted in 100 ml deionized distilled water to prepare an anchovy solution. The teeth were immersed in the anchovy solution for 5 min twice a day with 3 hours intervals. Immersions were repeated for 9 days. After immersion, the teeth were cut transversally through the window. The occlusal portions of the specimens were prepared for microscopic slides at ± 40um thickness. The cervical portions of the teeth were used as EDX specimens. Olympus BX41TF Fluorescence microscope was used to measure flourescence bandwidth. LEO scanning electron microscope with micro analyzer was used to measure flouride intrusion. Increment steps of 5um from outer edge of the enamel to inner side were used as the points of EDX analysis. Paired t-test was used to analyze the intrusion results. Results: Flouride intrusion depth measured using the flourescence method was 11.49 ± 0.71 um, while from the results of EDX analysis the average depth of flouride intrusion was 20.24 ± 0.57 um. Statistical analysis showed significant difference between the two methods. Conclusion: Intrusion measurement using EDX analysis gives higher flouride intrusion than the flourescence method.

Abstrak :
X-ray Fuorescence spectrometry semakin sering digunakan dalam bidang geokimia. X-Fuorescence spectrometry dikategorikan menjadi dua yakni ? WDXRF (wavelenght ? dispersive X- ray fluorescence spectrometer) dan EDXRF (energy-dispersive X ? ray fluorescence spectrometer). WDXRF dapat berbentuk sebagai sequential spectrometer, simultaneous spectrometer atau kelebihan dari kelebihan keduanya dikombinasikan menjadi satu perangkat yakni hibrid instrument. Masing-masing instrumen XFA mempunyai karakteristika dan kekhusussan dalam penggunaan. Penelitian ini menggunakan sequential spectrometer PW 1450 untuk menganalisis major, minor and trace elements dalam sample. Untuk mengkalibrasi PW 1450 digunakan 30 standar internasional dan 66 standar dari Institut für Mineralogie der Uni. Köln, Germany, yang telah diketahui konsentrasi masing-masing unsurnya. Interelement dan matrix effects dihilangkan dengan cara mencocokkan matrix pada sample dan standar, pengenceran, penambahan konsentrasi unsur-unsur yang dimaksud dalam jumlah tertentu, dan koreksi secara matematik pada saat analisis sedang berlangsung. Ujicoba pada dua sampel dan deskripsi statistik dengan standard deviation dan coefficient of variant menunjukkan bahwa XFA cukup akurat untuk beberapa unsur terutama unsur mayor, tetapi untuk Mg, Ca, K, Na, P, S, Co, Rb, Zn, Ni, Ba, Pb sensivitasnya masih lebih rendah dibandingkan dengan Atomic Absorpsion Spectrometry (AAS), Flame Emission Spectrometer (FES), Inductively Coupled Plasma (ICP) dan photometer.

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Wavelenght?Dispersive X-Ray Flourescence Accuration. X-Fuorescence spectrometry is a method, which is increasingly applied in the geochemical analysis. X-Fuorescence spectrometry is classified under two categories ? WDXRF (wavelenght ? dispersive X-ray fluorescence spectrometer) and EDXRF (energy-dispersive X ? ray fluorescence spectrometer). WDXRF can be configured as a sequential spectrometer , a simultaneous spectrometer or a hibrid instrument, which combines the advantages of the simultaneous and sequential spectrometers into one instrument. Each instrument is different in some characteristics, and each has applications for which it is specifically suited. In this investigation sequential spectrometer PW 1450 was used to analyze the major, minor and trace elements in the samples. The standards used in calibrating the PW 1450 for the analysis of all samples are materials of known composition (30 internatioanal standards and 66 standards from Institut für Mineralogie der Uni. Köln, Germany). Interelement and matrix effects are treated by matrix matching of samples and standards, dilution, preconcentration of the element of interest, and mathematic corrections during data analysis. The examination of two samples and the statistic description using standard deviation and coefficient of variant show that the XFA is accurate enaugh for many elements, especially for the major elements, but for Mg, Ca, K, Na, P, S, Co, Rb, Zn, Ni, Ba, Pb in comparison with Atomic Absorpsion Spectrometry (AAS), Flame Emission Spectrometer (FES), Inductively Coupled Plasma (ICP) and photometer it is less sensitive. It is posible to devaluate the errors by using coefficient of variant and standard deviation.