Wavelength-dependent light transmittance in resin composites: practical implications for curing units with different emission spectra.

Objectives: To evaluate light transmittance as a function of wavelength for eight composite materials and compare the transmittance for blue light produced from two curing units with different emission spectra.

Materials And Methods: Light transmittance through 2- and 4-mm-thick composite specimens was recorded in real time during 30 s of curing using a broad-spectrum (peaks at 405 and 450 nm) and a narrow-spectrum (peak at 441 nm) LED-curing unit. The spectral resolution of 0.

The effects of extended curing time and radiant energy on microhardness and temperature rise of conventional and bulk-fill resin composites.

Objectives: To investigate radiant energy, microhardness, and temperature rise in eight resin composites cured with a blue or violet-blue curing unit, using a curing protocol which exceeded manufacturer recommendations.

Materials And Methods: Cylindrical composite specimens (d = 8 mm, h = 2 or 4 mm, n = 5 per experimental group) were light-cured for 30 s. Light transmittance through specimens was recorded in real time to calculate radiant energy delivered to the specimen bottom.