If a good color effect on the enamel affected by chromatism is for you or for your patient the matter of utmost importance, then the appropriate issue will be the test facing. Three veneers in different colors are made on unprepped teeth to make sure of the required effect. Even on a processed tooth a single facing can be made in order to check the color, form, centre line and set-up in the arch.
The use of test facing will assure to your patient the adequate choice of the right color.