Radiopacity evaluation of commercial and experimental infiltrants with Bismute and ytterbium oxide addition and its influence on physical-chemical properties

Abstract

The aim of this study will be evaluate the addition influence of different concentrations of bismuth oxide (0, 30, 50% by weight) and ytterbium oxide particles (0, 30, 50% by weight) in the conversion degree, sorption and solubility, contact angle, flexural strenght, microradiography, energy dispersion X-ray spectroscopy and microtomographyof a commercially available infiltrant (Icon®, DMG, Germany) and experimental infiltrants. In order to evaluate the degree of conversion (n = 5), measurements before and after photoactivation of the samples will be performed in a Fourier Transform Infrared Spectrometer (FTIR). For sorption and solubility tests (n = 10), after dissecting, the polymerized samples will be weighed, stored in distilled water for 7 days and reweighed , after re-drying, until the final mass is obtained. The test to evaluate contact angle (n = 5) will be done using a goniometer. To evaluate flexural strength (n = 10) the universal test machine will be used. For analysis of the microradiopacity (n = 5) the specimens will be scanned by an image analysis system that is interconnected to a universal microscope. For energy-dispersive X-ray spectroscopy (n = 3), an EDX Link Analytical device coupled to a Zeiss scanning electron microscope will be used. For microtomography, enamel blocks of human molars (n = 80) will be used, which will be submitted to simulation of initial carious lesion in demineralizing/remineralizing solutions. Subsequently, the blocks will be infiltrated by the experimental infiltrators and ICON and submitted to penetration depth analysis (n = 5) by microtomography in the ¼-CT SkyScan scanner. The data will be analyzed by ANOVA and Tukey's test after analysis of homogeneity by the Levene test with significance level of 5%. (AU)