Contrast Ratios and Chromatic Value of IPS E.max LT Framework Materials
Cylindrical specimens of IPS E.max LT frameworks of C and D color series with a diameter of 13mm and thicknesses of 0.3mm and 0.5mm respectively were made with customized methods to determine the relative translucency and chromatic values. Reflectivity values (Yb and Yw) of all samples were determined with CM-5 chromatism instrument and contrast ratios (Yb/Yw) were then calculated. Chromatic values of IPS E.max LT blanks provided by the manufacturer were also determined. L valueS of ceramic blanks were significantly different among specimen groups (P < 0.01). From C1 to C4 and D2 to D4 L value declined. Contrast ratios were not significantly different for specimens of the same thickness and color series ranging from 0.3105 to 0.5134. Significant difference was found for specimens of different thicknesses but the same color (P < 0.05). Thickness is an important correlative factor for the relative translucency of IPS E.max LT framework materials.
Yiwang Bao, Danyu Jiang, Li Tian and Jianghong Gong
L. Q. Shao et al., "Contrast Ratios and Chromatic Value of IPS E.max LT Framework Materials", Key Engineering Materials, Vol. 492, pp. 354-357, 2012