title: A review of tooth colour and whiteness.
abstract: OBJECTIVE
  To review current knowledge on the definition of tooth whiteness and its application within dentistry, together with the measured range of tooth colours.
  
  
  METHODS
  'Medline' and 'ISI Web of Sciences' databases were searched electronically with key words tooth, teeth, colour, colour, white and whiteness.
  
  
  CONCLUSIONS
  The application of colour science within dentistry has permitted the measurement of tooth colour in an objective way, with the most common colour space in current use being the CIELAB (Commission Internationale de l'Eclairage). Indeed, many investigators from a range of different countries have reported L*, a* and b* values for teeth measured in vivo using instrumental techniques such as spectrophotometers, colorimeters and image analysis of digital images. In general, these studies show a large range in L*, a* and b* values, but consistently show that there is a significant contribution of b* value or yellowness in natural tooth colour. Further developments in colour science have lead to the description of tooth whiteness and changes in tooth whiteness based on whiteness indices, with the most relevant and applicable being the WIO whiteness index, a modified version of the CIE whiteness index.
authors.affiliation: Unilever Oral Care, Quarry Road East, Bebington, Wirral CH63 3JW, UK. Andrew.Joiner@Unilever.com
authors.forename: Andrew
authors.initials: A
authors.lastname: Joiner
authors.forename: Ian
authors.initials: I
authors.lastname: Hopkinson
authors.forename: Yan
authors.initials: Y
authors.lastname: Deng
authors.forename: Stephen
authors.initials: S
authors.lastname: Westland
mesh_terms: D003116:Color; D003124:Colorimetry; D006801:Humans; D007091:Image Processing, Computer-Assisted; D055095:Optics and Photonics; D013053:Spectrophotometry; D014070:Tooth / Q000033:anatomy & histology*