Direct Transmittance Characteristics of Resin -Composites

Objectives: The purpose of this study was to evaluate the effect of thickness and wavelength on direct transmittance of resin-composites. Methods: Four photo-cured disc samples (Ö20mm) and different thicknesses of three resin–composites (Grandio, Grandio Flow, and Grandio Seal) of the same shade, A3 were prepared. The direct transmittance measurements (n=3) were made using an Ocean Optics USB 4000 fibre optic Spectrometer operated by a Spectra Suite software. The spectra was analysed by mean values of the direct transmittance at intervals of 100nm wavelengths in a range 500-900nm.The differences in the direct transmittance values were determined by using One-way analysis of variance(ANOVA) combined with Tukey multiple test. Results: Significant differences (P<0.05) were found in the direct transmittance as both thickness and wavelength increases. Direct transmittance increases with increasing wavelength and decreases with increasing thickness. Conclusions: The significant differences in the direct transmittance with increasing wavelength and thickness of the materials will affect their clinical appearance.