Designing visually optimal shade guides.

Abstract

STATEMENT OF PROBLEM: Dental shade guides do not provide a broad coverage of tooth colors. There is a need for shade guides that can provide closer color matches. PURPOSE: The purpose of this study was to propose and assess a visually optimal shade guide for tooth color matching. MATERIAL AND METHODS: With the use of a spectrophotometric approach, the color distribution (L*a*b*) of 150 extracted human teeth and 3 commercially available shade guides (Vita Lumin V, Trubyte Bioform Color Order Shade Guide, and Vitapan 3D-Master Shade System) was measured. With the use of a hierarchical clustering approach, a series of shade guides was designed with a varying number of tabs. The average error (DeltaE) between colors from each shade guide and the extracted teeth was computed. RESULTS: The proposed visually optimal shade guide had the smallest average error of all guides tested. The new guide achieved lower error with fewer shade tabs than the 3 commercial systems evaluated. CONCLUSION: Within the limitations of this study, it was demonstrated that a hierarchical clustering technique can be used to design a visually optimal shade guide for a given population with a flexible degree of control over the mean error and number of tabs.