Edition V15N03 | Year 2018 | Editorial Artigo Original | Pages 176 to 185
Introduction: Dental ceramics are materials with satisfactory physical and chemical properties, but they can also cause attenuation of the blue light coming from photopolymerizers due to factors such as thickness, opacity, porosity, color and surface glaze, which justify the present study. Objective: to evaluate the light intensity through different types of ceramics, with different thicknesses, from two LED light curing units in different activation modes. Methods: A portable radiometer (Bluemeter®) was used to measure light intensities (in mW/cm2) from two different light curing units (Valo® in High and Xtra modes, and Bluephase G2® in High mode) through 50 ceramic discs of zirconium dioxide and high opacity lithium disilicate (HO), medium opacity (OM), low opacity (LO) and high translucency (HT), with 0.5-mm and 1.0-mm thickness, positioned between the tip of the light curing unit and the measurement sensor of the radiometer (n=5). Results: From the statistical analysis, it was observed that the attenuation of the light emitted by the photopolymerizers varied according to the different compositions of the ceramics, being the thickness a highly relevant factor in determining the results. Conclusion: The passage of light through the ceramic discs varied according to the modes of operation of the light-curing device. It was possible to conclude that the two studied factors interfere in the attenuation of the energy emitted by the light-curing units and that care with the type of ceramics and the type of light-curing unit must be observed in the step of choosing the cementing protocol.
Araújo KGR, Andreiuolo RF, Gonçalves SMRA, Correa IC. Effect of ceramic types and thicknesses on attenuation of light emission in different photoactivation modes. J Clin Dent Res. 2018 Sept-Dec;15(3):176-85. DOI: https://doi.org/10.14436/2447-911x.15.3.176-185.oar