title: Perceptibility and acceptability thresholds for colour differences in dentistry.
abstract: BACKGROUND
  Data on acceptability (AT) and perceptibility thresholds (PT) for colour differences vary in dental literature. There is consensus that the determination of ΔE* is appropriate to define AT and PT, however there is no consensus regarding the values that should be used. The aim of this clinical review was to provide a systematic approach to the topic of colour science of high clinical relevance to dental research.
  
  
  METHODS
  MEDLINE/PubMed, WoS and EBSCO databases were searched up to January 7, 2013; the outcome was restricted to English, and to clinical studies were spectrophotometers were used for measurement.
  
  
  RESULTS
  Forty-eight studies were eligible and met the inclusion criteria. Of the 48 studies there appeared to be a trend in their source references: 44% referred to the same study for the PT (ΔE*=1); and 35% referred to the same article for the AT (ΔE*=3.7).
  
  
  CONCLUSIONS
  More than half the studies defined PT as ΔE*=1, and one third of the studies referred to ΔE*=3.7 as the threshold at which 50% of observers accepted the colour difference. Most clinical studies refer to the same few in vitro literature that have attempted to determine PT and AT from decades ago.
authors: Department of Dental Materials Science, Academic Center for Dentistry Amsterdam, Amsterdam, The Netherlands; Department of Restorative Dentistry & Biomaterials Sciences, Harvard School of Dental Medicine, 188 Longwood Avenue, Boston, MA 02115, USA. Electronic address: G.Khashayar@acta.nl.
authors: Ghazal
authors: G
authors: Khashayar
authors: Department of Reference and Education Services, Harvard Countway Library of Medicine, 10 Shattuck St., Boston, MA 02115, USA.
authors: Paul A
authors: PA
authors: Bain
authors: Department of Restorative Dentistry & Biomaterials Sciences, Harvard School of Dental Medicine, 188 Longwood Avenue, Boston, MA 02115, USA.
authors: Samira
authors: S
authors: Salari
authors: Department of Dental Materials Science, Academic Center for Dentistry Amsterdam, Amsterdam, The Netherlands.
authors: Alma
authors: A
authors: Dozic
authors: Department of Dental Materials Science, Academic Center for Dentistry Amsterdam, Amsterdam, The Netherlands.
authors: Cornelis J
authors: CJ
authors: Kleverlaan
authors: Department of Dental Materials Science, Academic Center for Dentistry Amsterdam, Amsterdam, The Netherlands.
authors: Albert J
authors: AJ
authors: Feilzer
mesh_terms: D003116:Color; D003118:Color Perception / Q000502:physiology*; D006801:Humans; D012684:Sensory Thresholds / Q000502:physiology*; D013053:Spectrophotometry / Q000379:methods; D014070:Tooth / Q000033:anatomy & histology*
keywords: Aesthetic; Colour difference thresholds; Colour science; Spectrophotometry; Tooth Colour