To evaluate the in vitro interaction of the emission intensity of fluorescence between resin cement and glass-ceramic, changing the thickness of glass-ceramic.
Methods: Two self-etched resin cements were used: RelyX Unicem 2 Automix (3M ESPE) A2 VITA shade (RA2) and Translucent (RT) and SpeedCem (Ivoclar Vivadent) Transparent (SCT) and Yellow (SCY), such as disks of glass-ceramic IPS e.max Press HT A2 (Ivoclar Vivadent) and composite resin disks (Filtek Supreme XTE Body A 3,5) for a n=100. The glass ceramic disks were cut with a thickness of 1 mm and 0,5mm and were bonded to composite resin. Luminescence spectra were measured in a SPEX Fluorolog 212I spectrofluorometer. The spectra were collected with right angle geometry, in the s/r mode, and corrected for the wavelength dependence of the detector response. All spectra were obtained at room temperature with excitation at 380 nm. Student’s t-test and one-way-ANOVA followed by Tukey HSD (p<0.05) were computed for the statistical analysis.
Results:
Samples of 1mm: all groups showed similar values of fluorescence emission and the SCY 1 group is the one with higher fluorescence with a peak of 4,49E13 u.a. Samples of 0,5 mm: there is a slight difference between each group relative to fluorescence emission (p<0,001), and the SCT 0,5 group (1,06E14 u.a.) had the higher emission intensity of fluorescence. Within the same group of cements from each manufacturer and inside the same value, different thicknesses had statistically significant differences in the emission intensity of fluorescence: SCT 0,5 > SCT 1 (p<0,001); SCY 0,5 > SCY 1 (p=0,002); RT 0,5 > RT 1 (p=0,002); RA2 0,5 > RA2 1 (p=0,002).
Conclusions: The thickness of the ceramic influences the final emission intensity of fluorescence. The emission intensity of fluorescence of resin cements influenced the fluorescence of glass-ceramic.