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Tooth colour selection: the application of colour science to dental colour matching.

Existing dental shade guides are not arranged logically or scientifically and do not even correspond to measured tooth colour. Shade guides of all dental restorative materials are based on the long established porcelain shade guides which evolved to represent the available shades of porcelain teeth. The shades developed by a process of popular selection by which shades perceived to be nearer tooth colour were added and the least popular eliminated. This concept has not changed since the introduction of porcelain over two hundred years ago. The approach presented is fundamentally different with the colours evolved from measured tooth colour. By applying colour science a system for colour selection is developed specifically for tooth colour. Existing methods and problems are evaluated and the difficulties of colour matching quantified. A tooth colour order system is developed resulting in the construction of a tooth colour atlas assembled for easy use offering the accurate measurement of tooth colour and the potential of perfect colour matching.