ASTM E2466-06 - 15.1.2006
 
1. Scope

1.1 This test method covers the procedure, instrumental requirements, standardization procedures, material standards, measurement procedures, and parameters necessary to make precise measurements of in-vivo tooth color and tooth whiteness. In particular it is meant to measure the color of teeth in selected human subjects.

1.2 Digital images are used to evaluate tooth color of both posterior and anterior dentition (teeth). All other non-relevant parts, such as gums, spaces, etc., must be separated from the measurement and the analysis. All localized discoloration; such as stains, inclusions, etc., may be separated from the measurement and the analysis.

1.3 The broadband reflectance factors of teeth are measured. The colorimetric measurement is performed with a digital still camera while using an illuminator(s) that provides controlled illumination on the teeth. The measured data from a digital image are captured using a DSC. This test method is particularly useful for the gamut of tooth color which is:

1.3.1 CIE L* from 55 to 95,

1.3.2 CIE a* from 3 to 12,

1.3.3 CIE b* from 8 to 25 units.

1.4 The wavelengths for this test method include that portion of the visible spectrum from 400 to 700 nm.

1.5 Data acquired using this test method is for comparative purposes used during clinical trials or other types of research.

1.6 This test method is designed to encompass natural teeth, artificial teeth, restorations, and shade guides.

Note 1

This procedure may not be applicable for all types of dental work.

1.7 The apparatus, measurement procedure, data analysis technique are generic, so that a specific apparatus, measurement procedure, or data analysis technique may not be excluded.

1.8 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use.

 
2. Referenced Documents

E313-20

Standard Practice for Calculating Yellowness and Whiteness Indices from Instrumentally Measured Color Coordinates

E284-22

Standard Terminology of Appearance

D2244-23

Standard Practice for Calculation of Color Tolerances and Color Differences from Instrumentally Measured Color Coordinates

E308-22

Standard Practice for Computing the Colors of Objects by Using the CIE System

E179-17(2022)

Standard Guide for Selection of Geometric Conditions for Measurement of Reflection and Transmission Properties of Materials

Technical Report 2003-1

Guide to Material Standards and Their Use in Color Measurement

ISO 17321-1

Colour characterization of digital still cameras (DSCs) - Part 1: Stimuli, metrology, and test procedures

E1767-11(2022)

Standard Practice for Specifying the Geometries of Observation and Measurement to Characterize the Appearance of Materials

E1345-98(2019)

Standard Practice for Reducing the Effect of Variability of Color Measurement by Use of Multiple Measurements