Comparing L*a*b* color coordinates for natural teeth shades and corresponding shade tabs using a spectrophotometer.

It was investigated whether L*a*b* values for teeth as well as shade tabs for one 3D-Master shade were similar to one another. Teeth were measured using Vita Easyshade and L*a*b* values and the closest 3D shade was then recorded. The shade-guide tabs were also measured using the same device. 3D-Master shades yielded different L*a*b* values for the teeth than for the tabs. L* and a* values, especially, were systematically different. Therefore, Easyshade L*a*b* values for teeth and tabs could not be directly compared.