Spectrophotometric color evaluation of permanent incisors, canines and molars. A cross-sectional clinical study

Abstract

Background and aimsAn accurate color reproduction represents the final validation level of an esthetic anterior or posterior restoration. The aim of this study was to evaluate the color of permanent maxillary incisors, canines and molars, using a clinical spectrophotometer.MethodsThe Vita Easyshade Advance 4.0® intraoral spectrophotometer was used by one clinician to determine the color of 369 permanent maxillary incisors, canines and molars. The best matches to Vitapan Classical® and 3D-Master® shade guides were recorded. A one-way analysis of variance and Kruskal-Wallis test were used to compare L*, a*, b*, c* and h* color coordinates among the 3 types of teeth. Differences between the mean values of all color coordinates were evaluated by use of Bonferroni corrections. Color difference (ΔE*) between incisors, canines and molars was calculated from ΔL*, Δa* and Δb* data and the results were compared to ΔE*=3.3 acceptability threshold.ResultsExcept for Δa* and Δh* between canines and molars, statistically significant differences among the mean differences of all color coordinates were found when the 3 types of teeth were compared by pairs. The most frequently measured shades were A1 (48.4%), respectively 1M1 (31.5%) for incisors, B3 (36.6%), respectively 2M3 (39.8%) for canines and B3 (44.7%), respectively 2M3 (52%) for molars. Incisors had the highest lightness values, followed by canines and molars. Molars were the most chromatic with the highest a* and b* values.ConclusionsDespite the limitations of this study, color differences among incisors, canines and molars were found to be statistically significant, above the clinical acceptability threshold established. In conclusion, successful esthetic restorations of permanent teeth of the same patient need an individual color assessment and reproduction of every type of tooth.

Spectrophotometric Evaluation of Anterior Maxillary Tooth Color Distribution According to Age and Gender

“…Many studies have been conducted on the measurement and distribution of tooth color, and researchers have used both conventional and digital methods in their tooth color determinations . Digital devices can provide a standard measurement of the tooth and are more reliable .…”

“…Additionally, it was reported that the black and grey backgrounds simulated the conditions of the mouth better during color measurements . Other studies have made direct measurements without using any colors in the background . In our study, the anterior tooth color measurements were performed using a grey background to better simulate the oral condition.…”

“…The chroma refers to the intensity of the color . The CIE L * , a * , and b * (CIELab) system has also been used for tooth color related studies . This system has three coordinates to define the color: L * specifies the lightness and darkness of the color, while the a * and b * coordinates define the chromatic characteristics of the color.…”

“…In dentistry, the formula is used in color‐related research to compare the colors of two different restorations, or two different tooth colors . This formula evaluates the size of the color difference between the two colors numerically; however, it does not provide a sense of the direction of the color's coordinate axis …”

“…16,17 The CIE L * , a * , and b * (CIELab) system has also been used for tooth color related studies. 1,[18][19][20][21] This system has three coordinates to define the color: L * specifies the lightness and darkness of the color, while the a * and b * coordinates define the chromatic characteristics of the color. This system provides one with the ability to examine the color differences between two objects or teeth.…”