Prediction of optical efficacy of vital tooth bleaching using regression analysis

Abstract

Abstract Establishing a colorimetric guideline to predict the effectiveness of tooth bleaching could produce a more reliable dental treatment. The purpose of this study was to evaluate the effectiveness of tooth bleaching and to test the predictability of tooth color changes. A 10% carbamide peroxide bleaching system was used in studies at Harvard University and at Iwate Medical University in Japan. L *, a *, and b * values (CIELAB) for pre‐ and postbleaching were obtained and color differences (Δ E ) were calculated. The b * and L * values of the original tooth color indicated a relatively strong to moderate correlation with Δ E values, whereas a * showed a weak correlation. The multiple‐regression equation obtained from the color data of Harvard subjects performed better than the predictive model. The predicted Δ E correlated strongly with the observed Δ E ( r = 0.78). The validation of this equation on data collected from Iwate confirmed the strong correlation ( r = 0.74). © 2004 Wiley Periodicals, Inc. Col Res Appl, 29, 390–394, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20048