title: Evaluation of a newly developed visual shade-matching apparatus.
abstract: OBJECTIVE
  This study evaluated a newly developed visual shade-matching apparatus, Shademat Visual+, as well as the influence of tab arrangement, clinician gender, and years in practice on shade-matching quality.
  
  
  METHODS
  A group of 129 color-normal evaluators-dental students and general dentists-matched the shade of four ceramometal crowns using the Vitapan Classical shade guide. Crowns were positioned onto the upper member of an artificial head and fastened to the headrest of the dental chair or Shademat Visual+. Shade tabs were arranged according to the manufacturer's suggestion or according to deltaE* in relation to the "lightest" tab and divided into groups (alternative arrangement). The evaluators matched the shade of four ceramometal crowns both in daylight and using the Shademat Visual+ artificial light source. The color coordinates were determined using digital image analysis. Based on deltaE* values, each shade-matching result was ranked from 1 (the worst match) to 16 (the best match) points.
  
  
  RESULTS
  The evaluators achieved a better result in Shademat Visual+ trials than in daylight trials (13.2 points vs 12.4 points; P < .001). For the same ceramometal crown, 12.7 points were recorded in daylight trials with the manufacturer-suggested arrangement, and 13.7 were recorded with the alternative arrangement (P< .001). Corresponding values for Shademat Visual+ trials were 13.6 points and 14.6 points, respectively (P< .001). Female-male and student-dentist evaluator differences were not significant.
  
  
  CONCLUSIONS
  The Shademat Visual+ apparatus enabled better shade-matching results than daylight. The alternative tab arrangement enabled better results than the manufacturer-suggested one. Gender and years in practice did not influence shade-matching quality.
authors.affiliation: Department of Restorative Dentistry and Biomaterials, The University of Texas Health Science Center at Houston, Dental Branch, 77030-3402, USA. rparavina@uth.tmc.edu
authors.forename: Rade D
authors.initials: RD
authors.lastname: Paravina
mesh_terms: D000367:Age Factors; D003116:Color; D003118:Color Perception; D003442:Crowns; D017267:Dental Prosthesis Design / Q000295:instrumentation*; D005260:Female; D005792:General Practice, Dental; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008027:Light; D008029:Lighting; D008297:Male; D016876:Metal Ceramic Alloys / Q000737:chemistry; D017797:Prosthesis Coloring / Q000295:instrumentation*; D012737:Sex Factors; D013335:Students, Dental; D014070:Tooth / Q000033:anatomy & histology*
chemical_list: D016876:Metal Ceramic Alloys