Clinical Tooth Color Matching: In Vivo Comparisons of Digital Photocolorimetric and Spectrophotometric Analyses

Abstract

OBJECTIVE: This study aimed to compare the tooth color matching of two dental colorimetric methods: the spectrophotometric analysis (SPM) and the standardized digital photocolorimetric analysis (DPC). METHODS: The color of 60 maxillary central incisors of 30 volunteers (22.5 ± 7.6 years) was analyzed. In the DPC method, tooth photographs were standardized with the eLABor_aid protocol, processed with Adobe Photoshop Lightroom software, and the values of L*, a*, and b* were obtained with a Digital Color Meter software. For the SPM, L*, a*, and b* were measured directly with a handheld spectrophotometer. Data were submitted to paired t-test and Pearson correlation test (α=0.05). Mean color difference between the two methods was calculated with CIELAB formula. RESULTS: All color coordinates revealed different values when comparing DPC to SPM in the same tooth (p<0.0001). Mean color difference (ΔEab) between SPM and DPC was 11.5 ±3.1. A positive correlation was observed for L* (R2=0.73,p<0.0001), a* (R2=0.31, p=0.017), and b* (R2=0.83, p<0.0001). CONCLUSIONS: Even though the color coordinate values were different in both methods, they were correlated, revealing that the DPC is a viable alternative to determine the tooth color matching.