title: Data comparison between two dental spectrophotometers.
abstract: OBJECTIVE
  The objective of this study was to clinically test whether the data from two different spectrophotometers, based on spot and surface measurements, can be compared.
  
  
  METHODS
  Under standardized clinical conditions two devices (Vita Easyshade and Spectro Shade-Micro) were used to record the color of three areas (cervical, middle, and incisal) per tooth for three upper maxillary anterior teeth in 102 participants. Each position was measured three times to attain an average for the CIE L*a*b* coordinates and to attain the corresponding Vita Classical shade tab integrated in the software of both devices. Vita tabs were also described as L*a*b* values using earlier published translations so that color differences (ΔE) could be calculated between them.
  
  
  RESULTS
  The regression analysis between the two devices showed that the independent correlation coefficients of the L*a*b* values are low. Yet when the suggested shade codes are compared with Vita colors instead of L*a*b*, 40% of the cases were equal and 51% were clinically acceptable.
  
  
  CONCLUSIONS
  According to this study the two devices do not give a comparable shade selection output, and thus the exchange of L*a*b* values between the two spectrophotometers cannot be recommended.
authors.affiliation: Academic Centre for Dentistry Amsterdam, Dental Materials, Amsterdam, Netherlands. khashayar@acta.nl
authors.forename: G
authors.initials: G
authors.lastname: Khashayar
authors.forename: A
authors.initials: A
authors.lastname: Dozic
authors.forename: C J
authors.initials: CJ
authors.lastname: Kleverlaan
authors.forename: A J
authors.initials: AJ
authors.lastname: Feilzer
mesh_terms: D003116:Color; D003481:Cuspid / Q000033:anatomy & histology*; D017267:Dental Prosthesis Design / Q000295:instrumentation; D006801:Humans; D007180:Incisor / Q000033:anatomy & histology*; D055096:Optical Devices / Q000706:statistics & numerical data; D017797:Prosthesis Coloring / Q000295:instrumentation; D012044:Regression Analysis; D012984:Software / Q000706:statistics & numerical data; D013053:Spectrophotometry / Q000295:instrumentation* / Q000706:statistics & numerical data; D019237:Tooth Cervix / Q000033:anatomy & histology; D019228:Tooth Crown / Q000033:anatomy & histology