Influência da adição de sal de ônio na diminuição do amarelamento e nas propriedades de cimentos resinosos experimentais

Abstract

The aim of this study was to evaluate the effect of the addition of the Diphenyliodonium Hexafluorophosphate (DPI) on the properties of experimental lightcured resin cements and its influence on the color analysis. To the monomers base composition (1:1 mass ratio) Bisphenol A Diglycidyl Methacrylate (BisGMA) and Triethylene Glycol Dimethacrylate (TEGDMA) 0.1mol% Butylated Hydroxytoluene (BHT) was added as an inhibior. Camphorquinone (CQ) and Dimethylamino Ethyl Benzoate (EDAB) were added at 2 different concentrations with or without the addition of 0.5mol% DPI, resulting in eight groups: RC1 (0.5mol% CQ / EDAB1mol% without salt) , RC2 (0.5mol% CQ / 2mol% EDAB without salt), RC3 (1mol% CQ / 1mol% EDAB without salt), RC4 (1mol% CQ / 2mol% EDAB without salt), RC5 (0.5mol% CQ / 1mol% EDAB with salt), RC6 (0.5mol% CQ / 2mol% EDAB with salt), RC7 (1mol% CQ / 1mol% EDAB with salt), RC8 (1mol% CQ / 2mol% EDAB with salt). After the manipulation of the resinous matrix, 60wt% of silanated bariumaluminum-silicate glass was added as a filler. The studied properties were the following: Degree of Conversion (DC) (n=5) by Fourier transformed infrared spectrometer; L*a*b* Color Analysis (Y) by reflectance spectrophotometer with CIELab system; Sorption (WS) and Solubility (S) in distilled water (n=5); Flexural Strength (FS) and Modulus of elasticity (E) (n=10). Statistical analysis (α=0.05) was performed for each test separately by ANOVA three way and Tukey's test. MannWhitney were used for color analysis (L* variable). The results showed that the addition of the DPI increased the degree of conversion and L* without increasing the sorption and the values of a*b* in cements containing 0.5mol% CQ. 1mol% CQ concentration showed higher values of b* and the lower sorption without salt. Groups with EDAB 2mol% showed a higher DC. S, FS and E showed no statistical differences. It can be concluded that the addition of the DPI allows the reduction of the CQ with a lower yellowing effect, maintaining adequate properties in the experimental cements tested.