Describe the tools and equipment that can be used when matching and communicating a shade.

Describe the tools and equipment that can be used when matching and communicating a shade.

1. • The measurement of tooth colour is possible through a number of methods including visual assessment with shade guides, spectrophotometry, colorimetry and computer analysis of digital images.

2. • Vita classic shade guide is the most common shade guide, arranged by HUE. Vita 3D shade guide uses the Munsell colour system - HUE, CHROMA, VALUE.

3. • The Vita 3D‐Master shade guide features a systematic colorimetric distribution of 26 shade tabs within the tooth colour space. The manufacturer purports that this shade guide demonstrates an equidistant distribution in the colour space. The shade guide is organized into five primary value levels, with a secondary distribution based on chroma and hue. These value groups are arranged from the lightest (value level 1) to the darkest (value level 5), left to right.

4. • Technology based shade matching devices include Digital cameras, Spectrophotometers and Colorimeters. Spot measurement (SM) devices measure a small area on the tooth surface, while complete‐tooth measurement (CTM) devices measure the entire tooth. Measurement of the complete surface gives the operator more consistent and reproducible information about the tooth structure.

5. • Digital cameras capture images using charged coupled devices, which contain millions of microscopically small light‐sensitive elements. The advantage of this method is that the camera records each of the three colours at each pixel location.

6. • A spectrophotometer can be held against a tooth to match shade. A spectrophotometer measures and records the amount of visible radiant energy reflected or transmitted by an object one wavelength at a time for each value, chroma and hue present in the entire visible spectrum.

7. • Filter colorimeters generally use three or four silicon photodiodes that have spectral correction filters. These filters act as analogue function generators that limit spectral characteristics of light striking the detector surface.

8. • Digital impression intraoral scanners such as Trios, includes tooth stain shades, which can be sent directly to the lab with internet.