Title: 0710 - From Blue to Red: Dental Composites Light-cured by Long Wavelengths
Dayane Oliveira (Presenter)
Piracicaba Dental School, State University of Campinas
Mateus Rocha, Piracicaba Dental School, State University of Campinas
Alexandre Silvino, Institute of Macromolecules Professor Eloisa Mano, Federal University of Rio de Janeiro
Americo Correr, Piracicaba Dental School, State University of Campinas
Mario Sinhoreti, Piracicaba Dental School, State University of Campinas
Jean-Francois Roulet, College of Dentistry, University of Florida
Objectives: The aim of this study was to develop and characterize dental resin composites light-cured by long wavelengths (green/red light).
Methods: New photoinitiators were synthetized to absorb light within green/red spectra. These photoinitiators were characterized by UV-vis spectrophotometry, FT-IR and NMR. Model resin-based composites were produced containing either the alternative photoinitiators synthetized or the conventional photoinitiator, camphorquinone, as a control. To state the differences between short and long wavelengths, LED curing lights emitting blue, green or red light were developed and characterized by spectrophotometry and digital thermal analysis. The light-transmittance of the different wavelengths through the resin-based composites was also evaluated. The degree of conversion of the resin-based composites was evaluated by FT-IR spectroscopy. Degree of conversion was evaluated at the top and the bottom of samples with thicknesses from 2 to 5mm.
Results: Long wavelengths showed higher light-transmittance through the composites than short wavelengths (p<0.001). Long wavelengths also presented lower temperature rise during light exposure in comparison to short wavelengths (p<0.001). The composites light-cured by long wavelengths were capable of providing similar or higher degree of conversion in comparison to the composite light-cured by short wavelength, but increased depth of cure.
Conclusions: Composites light-cured by long wavelengths seem to be suitable for use in Dentistry and bring benefits such as higher depth of cure and less heating during light exposure.
This abstract is based on research that was funded entirely or partially by an outside source:
FAPESP grant #2016/05823-3 and #2017/22161-7
The submitter must disclose the names of the organizations with which any author have a relationship, the nature of the relationship, and the clinical or research area involved. The following is submitted: None