Patent ID: 7301636

Claim:
A method for shade matching a dental object and reporting a shade via an output device comprising the steps of: determining a polygon in color space for each shade of a plurality of shades in a shade system; taking at least one color measurement of the dental object; determining if the color measurement of the dental object is within the polygon for each shade of the plurality of shades in the shade system; if the color measurement is within the polygon of one shade of the plurality of shades in the shade system, then reporting via the output device the one shade as a principal shade of the dental object; if the color measurement is within the polygon of more than one shade of the plurality of shades in the shade system, then reporting via the output device as the principal shade of the dental object a shade of the more than one shade that has a lowest ΔE, wherein the ΔE is calculated for each of the more than one shade based on the color measurement and on a color value for each of the more than one shade; and if the color measurement is not within any polygon of any shade of the plurality of shades in the shade system, then reporting via the output device as the principal shade a shade for which the distance between the color measurement in color space and a nearest edge of the polygon for that shade has the lowest value.