title: Efficacy of a computerized shade selection system in matching the shade of anterior metal-ceramic crowns--a pilot study.
abstract: OBJECTIVE
  The purpose of this study was to determine whether anterior crowns fabricated using a computerized shade selection system (ShadeScan, Cynovad) (experimental procedure) match adjacent teeth better than anterior crowns fabricated using conventional shade prescription and clinical slides (control).
  
  
  METHODS
  Five subjects who required a crown to restore a maxillary central incisor were selected. Two metal-ceramic crowns were fabricated for each incisor, 1 using the experimental procedure and 1 using the control method. The shade selection method to be used for the first and second crowns was randomly assigned. The duration of each procedure was recorded. Each restoration was tried-in in a double-blind manner and evaluated for its level of match to adjacent teeth using modified Ryge criteria. Data were analyzed within each subject using descriptive statistics and paired t test (alpha = .05).
  
  
  RESULTS
  In 40% of the cases, both procedures did equally well. In the remaining 60% of the cases the control procedure (two-thirds of the cases) performed better than the experimental procedure (one-third of the cases). Duration of the control procedure was 14.4 +/- 5 minutes, and the experimental procedure was 5.2 +/- 3.3 minutes. A paired t test showed the difference was significant (P = .0045).
  
  
  CONCLUSIONS
  The level of matching of crowns fabricated with the ShadeScan system was not different from crowns fabricated using the control. However, it took significantly less time to record the shade with the ShadeScan system.
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, University of Washington, D 780 Health Sciences Center, 1959 NE Pacific Street, Box 357456, Seattle, WA 98195, USA. araigrod@u.washington.edu
authors.forename: Ariel J
authors.initials: AJ
authors.lastname: Raigrodski
authors.forename: Gerard J
authors.initials: GJ
authors.lastname: Chiche
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Aoshima
authors.forename: Charles F
authors.initials: CF
authors.lastname: Spiekerman
mesh_terms: D003116:Color; D018592:Cross-Over Studies; D003442:Crowns; D003658:Decision Making, Computer-Assisted; D004311:Double-Blind Method; D006801:Humans; D016876:Metal Ceramic Alloys / Q000737:chemistry; D010865:Pilot Projects; D017797:Prosthesis Coloring
chemical_list: D016876:Metal Ceramic Alloys