Shading Vita YZ substructures: influence on value and chroma, part I

All-ceramic restorations should reproduce as well as possible the color of the natural teeth to create a restoration in accordance with the esthetic wishes and ideas of the patient. The basic color of zirconium oxide is white to ivory. The color can be partially adapted by veneering it with ceramic materials. However, it would be better if the substructure could already be adapted to the basic color shade of the neighboring teeth. In this study, the influence of differently shaded frameworks made of Y-TZP by Vita and 3M ESPE and by Enrico Steger (without, with 0.5 mm, or with 1.0 mm ceramic veneer with Base Dentin) on the brightness, saturation, and color shade (= value, chroma, and hue) was measured and assessed with the aid of a spectral photometer (EasyShade, Vita) in a clinical case in the mouth and on the model. By adaptation to the basic shade, the shading of substructures made of Y-TZP can help to reduce the necessary layer thickness of the veneer ceramic to achieve the desired color and should be performed in the future as a matter of routine. In this way, more substance can be conserved when restoring the teeth without having to accept an impairment of the esthetic result.