IADR Abstract Archives
Optical Properties of Resin Composites Containing Different Size Supra-nano Spherical Fillers
Objectives: Spherical particles smaller than the wavelength of visible light can generate inherent structural color in dental composites, without incorporating additional pigmentation. The aim of this study was to evaluate the relationship between filler size and structural color in a series of resin composites, and compared to natural teeth.
Methods: Three types of uniform-sized supra-nano spherical fillers were prepared (Tokuyama Dental, Japan). SEM was used to measure filler size (n=30). Experimental resin composites were produced with TEGDMA/UDMA as matrix monomers, camphorquinone/amine as photoinitiator and 65 wt% of each filler. 2.0 mm thick specimens were made in 8 mm diameter molds. The composites were light-cured for 20 seconds (Eliper S10 LED Curing Light, 3M ESPE; 10 mm tip; 800 mW/cm2) through polypropylene film. After storage in water at 37°C for 1 week, spectral reflectance of each specimen from 400 nm to 700 nm was measured on a black background (n=5) with a spectrophotometer (D65 illuminant; CM-700d, Minolta, Japan). The spectral reflectance of 10 extracted molars was similarly measured.
Results: The filler diameters were 162±6nm, 264±5nm and 302±5nm. Spectral reflectance varied with filler size (Fig. 1): 264 nm filler produced peaks ∼540 nm (green to yellow) and remained elevated to a peak ∼700 nm (red), 162 nm filler produced a peak ∼420 nm (blue), and 302 nm filler produced peaks ∼440 nm and remained high beyond 550 nm. The average spectra of the teeth was most similar to that of the composite with the 260 nm filler.
Conclusions: This study shows that inclusion of uniformed sized supra-nano spherical filler in resin composite can generate structural color unique to the filler size. Specifically, inclusion of spherical particles around 260 nm can generate yellowish to reddish structural color that is most similar to natural teeth.
Methods: Three types of uniform-sized supra-nano spherical fillers were prepared (Tokuyama Dental, Japan). SEM was used to measure filler size (n=30). Experimental resin composites were produced with TEGDMA/UDMA as matrix monomers, camphorquinone/amine as photoinitiator and 65 wt% of each filler. 2.0 mm thick specimens were made in 8 mm diameter molds. The composites were light-cured for 20 seconds (Eliper S10 LED Curing Light, 3M ESPE; 10 mm tip; 800 mW/cm2) through polypropylene film. After storage in water at 37°C for 1 week, spectral reflectance of each specimen from 400 nm to 700 nm was measured on a black background (n=5) with a spectrophotometer (D65 illuminant; CM-700d, Minolta, Japan). The spectral reflectance of 10 extracted molars was similarly measured.
Results: The filler diameters were 162±6nm, 264±5nm and 302±5nm. Spectral reflectance varied with filler size (Fig. 1): 264 nm filler produced peaks ∼540 nm (green to yellow) and remained elevated to a peak ∼700 nm (red), 162 nm filler produced a peak ∼420 nm (blue), and 302 nm filler produced peaks ∼440 nm and remained high beyond 550 nm. The average spectra of the teeth was most similar to that of the composite with the 260 nm filler.
Conclusions: This study shows that inclusion of uniformed sized supra-nano spherical filler in resin composite can generate structural color unique to the filler size. Specifically, inclusion of spherical particles around 260 nm can generate yellowish to reddish structural color that is most similar to natural teeth.
IMAGES
3177762_File000000.jpg
3177762_File000000.jpg