IADR Abstract Archives
Fluorescence Characteristics of Dental Zirconia
Objectives: To mimic the optical appearance of natural teeth, dental materials need an adequate fluorescence. Colored zirconia materials were lacking this feature for a long time and only recently it has been implemented [M. Jahns, et al., IADR2017]. The characteristics of fluorescent zirconia (3M™ Lava™ Esthetic Fluorescent Full-Contour Zirconia) will be analyzed in more detail and compared to human dentin and other materials.
Methods: Disc-shaped specimens (6mm diameter, 0.5mm thickness) were prepared (slicing or casting, as appropriate). If applicable (use instructions), specimens were heat-treated. Tested materials were Lava™ Esthetic A1 (3M), Lava Esthetic Zirconia A3.5 (3M), 3M™ Lava™ Ultimate CAD/CAM Restorative A2 HT, e.max® Press HT A2 (Ivoclar Vivadent), e.max® Glaze Paste Flu (Ivoclar Vivadent). Specimens were analyzed for their fluorescence emission and excitation spectra with a SpectraMAX M2e, Molecular Devices.
Results: Tested materials have excitation maxima at different wavelengths: Lava Esthetic Zirconia 310nm, dentin 340nm, e. max® Press 360nm, e.max® Glaze Paste Flu 350nm and Lava Ultimate 320nm and 380nm, Fig. 1. The effect of different excitation conditions (light sources) is summarized in Fig. 2. Intensities of all materials vary from each other and are dependent on the light source, most prominently in case of Lava Esthetic where a 368nm LED induces about a about a third of the intensity obtained with daylight.
Conclusions: Different materials show fluorescence excitation spectra with individual characteristics (excitation maxima). Fluorescence intensities depend on both, the used dental material and the applied light source. Especially light sources with narrow emission spectra, like LEDs, often lead to intensities lower than obtained under daylight. This effect is most prominent for the investigated zirconia material. In the most typical use situation, however, under daylight, Lava Esthetic Zirconia shows similar fluorescence intensity like human dentin
Methods: Disc-shaped specimens (6mm diameter, 0.5mm thickness) were prepared (slicing or casting, as appropriate). If applicable (use instructions), specimens were heat-treated. Tested materials were Lava™ Esthetic A1 (3M), Lava Esthetic Zirconia A3.5 (3M), 3M™ Lava™ Ultimate CAD/CAM Restorative A2 HT, e.max® Press HT A2 (Ivoclar Vivadent), e.max® Glaze Paste Flu (Ivoclar Vivadent). Specimens were analyzed for their fluorescence emission and excitation spectra with a SpectraMAX M2e, Molecular Devices.
Results: Tested materials have excitation maxima at different wavelengths: Lava Esthetic Zirconia 310nm, dentin 340nm, e. max® Press 360nm, e.max® Glaze Paste Flu 350nm and Lava Ultimate 320nm and 380nm, Fig. 1. The effect of different excitation conditions (light sources) is summarized in Fig. 2. Intensities of all materials vary from each other and are dependent on the light source, most prominently in case of Lava Esthetic where a 368nm LED induces about a about a third of the intensity obtained with daylight.
Conclusions: Different materials show fluorescence excitation spectra with individual characteristics (excitation maxima). Fluorescence intensities depend on both, the used dental material and the applied light source. Especially light sources with narrow emission spectra, like LEDs, often lead to intensities lower than obtained under daylight. This effect is most prominent for the investigated zirconia material. In the most typical use situation, however, under daylight, Lava Esthetic Zirconia shows similar fluorescence intensity like human dentin
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