Evaluation of Whiteness Formulae for Teeth

In this study, various whiteness and yellowness indices were compared on their performance of measuring the whiteness of human teeth. Psychophysical experiments were conducted by 9 observers on teeth whiteness perception. According to visual results, the Pearson correlation coefficient and ‘% wrong decision’ method were applied to determine the best index for teeth whiteness measurement. A modified version of whiteness formula (WIO) was introduced by optimising the original CIE whiteness formula (WIC) and it was found that WIO is the most suitable index for predicting the whiteness of teeth.