Effect of thickness of CAD/CAM materials on light transmission and resin cement polymerization using a blue light-emitting diode light-curing unit.

Autor: de Castro EF; Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil., Fronza BM; Department of Biomaterials and Oral Biology, School of Dentistry, University of São Paulo, São Paulo, Brazil., Soto-Montero J; Department of Restorative Dentistry, School of Dentistry, Universidad de Costa Rica, San Pedro, Costa Rica., Giannini M; Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil., Dos-Santos-Dias CT; Department of Exact Sciences, College of Agriculture, 'Luiz de Queiroz'/University of São Paulo, Piracicaba, Brazil., Price RB; Department of Dental Clinical Sciences, School of Dentistry, Dalhousie University, Halifax, Canada.
Jazyk: angličtina
Zdroj: Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.] [J Esthet Restor Dent] 2023 Mar; Vol. 35 (2), pp. 368-380. Date of Electronic Publication: 2022 Jul 27.
DOI: 10.1111/jerd.12946
Abstrakt: Objective: Evaluate the effect of thickness of high-translucency (HT) CAD/CAM materials on irradiance and beam profile from a blue light-emitting diode light-curing unit (LCU) and on the degree of conversion (DC) and maximum polymerization rate (Rp max ) of a light-cured resin cement (LCC).
Material and Methods: The direct output from the LCU, the light transmission and irradiance ratio (IR) through one conventional composite and nine HT CAD/CAM materials (0.5, 1.0, 1.5, or 2.0-mm thick; n = 5) were measured with a integrating sphere coupled to a spectrometer. The light beam was assessed with a beam profiler camera. The DC at 600 s and the Rp max of one LCC was determined using a Fourier transform infrared spectrometer (n = 5). Data were analyzed by ANOVA followed by Tukey's tests, and Dunnett's test was also used for irradiance data (α = 0.05).
Results: A significant decrease in irradiance through all materials occurred as thickness increased. Thin CAD/CAM materials improved light homogeneity, which decreased with the increase in thickness. The DC of the LCC directly exposed to light was the same as when exposed to 45%, 25%, 15%, or 5% IRs. Rp max decreased with the decrease in IR.
Conclusions: Although the HT CAD/CAM materials reduced the irradiance from the LCU, minor effects were observed in the LCC's DC.
Clinical Significance: Despite the light attenuation of blue light through different CAD/CAM materials that were up to 2-mm thick, the degree of conversion of one brand of light-cured resin cement was clinically acceptable when the LCU was used for 30 s.
(© 2022 Wiley Periodicals LLC.)
Databáze: MEDLINE
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