Light energy transmission and Vickers hardness ratio of bulk-fill resin based composites at different thicknesses cured by a dual-wave or a single-wave light curing unit.

Purpose: To quantify light energy transmission through two bulk-fill resin-based composites and to measure the top to bottom surface Vickers hardness ratio (VHratio) of samples of various incremental thicknesses, using either a single-wave or dual-wave light curing unit (LCU).

Methods: Tetric EvoCeram Bulk Fill (TECBF) and SonicFill (SF) were studied. Using MARC-RC, the irradiance delivered to the top surface of the samples 2, 3, 4 and 5 mm thick (n= 5 for each thickness) was adjusted to 800 mW/cm2 for 20 seconds (16 J/cm2) using either a single-wave, Bluephase or a dual-wave, Bluephase G2 LCUs.

The influence of two different curing regimens on light energy transmission through bulk-fill resin composites and Vickers hardness.

Purpose: To compare the total light energy transmission (J/cm2) through bulk-fill composite materials (BFMs) and Vickers hardness (VH) using a single-peak light curing unit (LCU) using two curing regimens.

Methods: Samples (n= 5) of viscous BFMs, Tetric EvoCeram Bulk Fill (TBF), X-tra fil (XF), and flowable BFMs, SureFil SDR (SDR), and X-tra base (XB) were prepared in 4 mm deep rings. The control was Tetric EvoCeram (TEC), a conventional composite.

Light energy attenuation through orthodontic ceramic brackets at different irradiation times.

Objective: To evaluate the total light energy (TLE) transmission through three types of ceramic brackets with, bracket alone and with the addition of orthodontic adhesive, at different exposure durations, and to compare the microhardness of the cured adhesive.

Materials And Methods: Three different makes of ceramic brackets, Pure Sapphire(M), Clarity™ ADVANCED(P) and Dual Ceramic(P) were used. Eighteen specimens of each make were prepared and allocated to three groups (n = 6).