title: Precision of in vivo colorimetric assessments of teeth.
abstract: OBJECTIVE
  The repeatability of an intraoral positioning device for a tristimulus photoelectric colorimeter was assessed with the left maxillary central incisors of seven subjects.
  
  
  METHODS
  Intraclass correlation coefficients and repeatability color differences were determined from repeated color measurements made by the same examiner on 3 separate days. Interexaminer repeatability was tested by comparing CIELAB measurements of the same tooth made by two different examiner combinations, both using the positioning device.
  
  
  RESULTS
  High intraclass correlation coefficients were demonstrated for intraexaminer and interexaminer repeatability. Repeatability color differences were 0.34 delta E units for intraexaminer assessments, whereas interexaminer repeatability color differences were 0.13 and 0.61 delta E units for the two examiner pairs.
  
  
  CONCLUSIONS
  It was concluded that a colorimeter, equipped with a custom positioning jig, had acceptable precision for intraoral measurement of longitudinal changes in tooth color.
authors.affiliation: University of Manitoba, Winnipeg, Canada.
authors.forename: R D
authors.initials: RD
authors.lastname: Douglas
mesh_terms: D000704:Analysis of Variance; D002138:Calibration; D003116:Color; D003124:Colorimetry / Q000295:instrumentation / Q000379:methods / Q000706:statistics & numerical data; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007180:Incisor / Q000033:anatomy & histology*; D008027:Light; D008297:Male; D008437:Maxilla; D015588:Observer Variation; D011336:Probability; D015203:Reproducibility of Results