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[Shade selection in fixed prosthodontics].

Shade selection is a crucial clinical step during prosthetic treatment. Nevertheless, because it is based on subjective criteria, very often the esthetic result is compromised due to inadequate color reproduction. In order to explore this complicated problem, this paper attempts to analyse it as scientifically as possible. Initially, the physical phenomenon of "Color" is analysed. Color depends upon the light source, the object and the observer. Metamerism is the fatal enemy in shade matching. Shade selection through the use of shade guides is inadequate due to lack of standardization. Therefore the possibilities of improved application of the available materials are thoroughly explored for both simple and more complicated cases. Best results can be achieved by segmental color selection (separately for dentin and enamel).