title: In vivo and in vitro assessment of an intraoral dental colorimeter.
abstract: OBJECTIVE
  The purpose of this study was to assess the performance of an intraoral dental colorimeter.
  
  
  METHODS
  In vivo repeatability of an intraoral colorimeter was assessed by performing color measurements of 30 individuals' right maxillary central incisor. Three consecutive measurements from each individual were made. In the in vitro part of the study, 25 metal-ceramic and 25 all-ceramic specimens were prepared. Five shades of metal-ceramic and all-ceramic specimens were selected for color determination. A widely recognized in vitro colorimeter was used as the control group for the in vitro performance assessment of the in vivo colorimeter. The color differentiation capability of two colorimeters was compared with the readings obtained from ceramic specimens. DeltaE values between shade groups of ceramic specimens were calculated and statistically analyzed with Student's t-test. The repeatability of the intraoral instrument was evaluated statistically with Intraclass correlation coefficient.
  
  
  RESULTS
  The in vivo evaluation results showed that the overall repeatability coefficient values of L*, a*, and b* notations of the intraoral colorimeter were "excellent." The color differences (DeltaE) calculated between the colorimeters were significant only between shades A(1)-B(1) for metal-ceramic specimens (p= 0.002); however, from 5 of 10 shade couples of all-ceramic specimens, the color differences obtained from the readings of the in vivo colorimeter were significantly different from that of the in vitro colorimeter (p < 0.001). For all specimens, the differences between DeltaE values were within clinically acceptable limits (<3.5).
  
  
  CONCLUSIONS
  Within the limitations of this study, the intraoral colorimeter exhibited successful in vivo repeatability; however, the color difference detection performance of the device varied depending on the translucency of the specimens.
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, Ankara University, Ankara, Turkey.
authors.forename: Lale
authors.initials: L
authors.lastname: Karaagaclioglu
authors.forename: Hakan
authors.initials: H
authors.lastname: Terzioglu
authors.forename: Burak
authors.initials: B
authors.lastname: Yilmaz
authors.forename: Bengul
authors.initials: B
authors.lastname: Yurdukoru
mesh_terms: D000328:Adult; D003124:Colorimetry / Q000295:instrumentation*; D003748:Dental Equipment; D003776:Dental Porcelain; D005260:Female; D006801:Humans; D007180:Incisor; D008297:Male; D008437:Maxilla; D016876:Metal Ceramic Alloys; D055620:Optical Phenomena; D017797:Prosthesis Coloring; D015203:Reproducibility of Results; D055815:Young Adult
chemical_list: D016876:Metal Ceramic Alloys; D003776:Dental Porcelain