Color comparison between non-vital and vital teeth

PURPOSE

The aim of this study was to define a color space of non-vital teeth and to compare it with the color space of matched vital teeth, recorded in the same patients.

MATERIALS AND METHODS

In a group of 218 patients, with the age range from 17 to 70, the middle third of the buccal surface of 359 devitalized teeth was measured using a clinical spectrophotometer (Vita Easyshade Advance). Lightness (L^*), chromatic parameters (a^*, b^*), chroma (C^*), hue angle (h) and the closest Vita shade in Classical and 3D Master codifications were recorded. For each patient, the same data were recorded in a vital reference tooth. The measurements were performed by the same operator with the same spectrophotometer, using a standardized protocol for color evaluation.

RESULTS

The color coordinates of non-vital teeth varied as follows: lightness L^*: 52.83–92.93, C^*: 8.23–58.90, h: 51.20–101.53, a^*: −2.53–24.80, b^*: 8.10–53.43. For the reference vital teeth, the ranges of color parameters were: L^*: 60.90–97.16, C^*: 8.43–39.23, h: 75.30–101.13, a^*: −2.36–9.60, b^*: 8.36–39.23. The color differences between vital and non-vital teeth depended on tooth group, but not on patient age.

CONCLUSION

Non-vital teeth had a wider color space than vital ones. Non-vital teeth were darker (decreased lightness), more saturated (increased chroma), and with an increased range of the hue interval. An increased tendency towards positive values on the a^* and b^* axes suggested redder and yellower non-vital teeth compared to vital ones.