The evolution of dental ceramics and adhesive procedures allowed the development of all-ceramic
restorations and more conservative preparation designs. These restorations are largely affected by factors
as substrate shade, cement, ceramic thickness, ceramic shade, and ceramic translucency. Instrumental
shade evaluation using spectrophotometers provides objective data that is used for shade evaluation and
matching. However, there is no method to combine the CIELab coordinates (L*, a*, b*) obtained from the
tooth substrate and ceramic to predict the best ceramic type, shade, and thickness. The understanding of
these interactions would extend the use of spectrophotometers in dentistry.