RESEARCH ARTICLE
Precision of a Reflectance Spectrophotometer in Measuring Anterior Tooth Color
Effimia Koumpia1, *, Athanasios E. Athanasiou2, Theodore Eliades3, Michael Knösel4
Article Information
Identifiers and Pagination:
Year: 2018Volume: 12
First Page: 884
Last Page: 895
Publisher ID: TODENTJ-12-884
DOI: 10.2174/1874210601812010884
Article History:
Received Date: 26/5/2018Revision Received Date: 06/9/2018
Acceptance Date: 1/10/2018
Electronic publication date: 30/10/2018
Collection year: 2018
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: (https://creativecommons.org/licenses/by/4.0/legalcode). This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
Background:
Intraorally, a common instrumental approach for measuring tooth color is reflectance spectrophotometry.
Objective:
To evaluate the precision of a reflectance spectrophotometer in accurately measuring anterior tooth color.
Methods:
The twelve labial surfaces of the anterior teeth of sixteen patients were measured spectrophotometrically (SpectroShadeTM Micro) on three non-consecutive days (1st, 2nd, 8th). Tooth color was converted to L*, a* and b* colorimetric values; intra-examiner repeatability was assessed in ΔΕ-units between two same day repeated measurements. Intra-examiner reproducibility was measured for the effect of tooth type, time and their interaction.The linear effect of the acquisition angle on the colorimetric values of each tooth was also estimated.
Results:
The highest values of systematic or random error occurred for teeth #33, #43 and #32. There were no statistically significant differences in systematic or random errors for any tooth between the three measurement days. Statistically significant differences were found for tooth type (p=0.039), whereas time and tooth and time interaction were not statistically significant. A statistically significant linear correlation was found between the L* and a* values and the acquisition angle for teeth #12 and #31, (p<0.008).
Conclusion:
The reflectance spectrophotometer provided a precise measurement of tooth color in-vivo since the systematic and random errors generated were below the threshold for perceivable color mismatches (ΔΕ<1). In rejection of the null hypotheses, the tooth type (maxillary central incisors) and variation of the acquisition angle of image capture (L* and a* parameters in teeth #12 and #31) affected the reproducibility of intraoral spectrophotometric measurements.
