title: [Effect of Shofu gingival matrices which simulate the gingival color on spectrophotometric tooth color measurement].
abstract: OBJECTIVE
  To investigate the effect of gingival color on spectrophotometric color measurement in a standardized model.
  
  
  METHODS
  Shofu gingival matrices were used to simulate the soft tissue and VITA Classical shade tabs were fixed into them. Both the gingival matrices and shade tabs were measured with Crystaleye spectrophotometer in a black box. Regions of the shade tabs, gingival color and their combinated effect on measurements were analyzed, Pearson correlation analysis was used to identify the correlation of the gingival color difference with the shade tabs color difference.
  
  
  RESULTS
  The ranges of color difference were 1.01-2.26 in the cervical, 0.93-1.27 in the body and 1.67-2.97 in the incisal regions, respectively. Statistical analysis revealed that there was significant difference among all the gingival groups in the cervical region. Color differences were similar in the body and the incisal regions. The color measurement with Crystaleye was influenced by the regions of the shade tabs, the gingival color and their combination (P<0.001). Pearson Correlation Coefficient was 0.646 in the cervical, 0.386 in the body and 0.217 in the incisal regions respectively(P<0.001).
  
  
  CONCLUSIONS
  The color measurement in the cervical region with the spectrophotometer was influenced by the color of the simulated gingiva. Such influence was not obvious in the body and incisal regions. Color coordinates changed regularly with the gingival color.
authors.affiliation: Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing 100081, China.
authors.forename: Li
authors.initials: L
authors.lastname: Chen
authors.forename: Xu
authors.initials: X
authors.lastname: Yang
authors.forename: Jian-guo
authors.initials: JG
authors.lastname: Tan
authors.forename: Jian-feng
authors.initials: JF
authors.lastname: Zhou
authors.forename: Yang
authors.initials: Y
authors.lastname: DU
authors.forename: Fang-ping
authors.initials: FP
authors.lastname: Wang
mesh_terms: D003116:Color / Q000592:standards*; D003118:Color Perception; D003124:Colorimetry / Q000379:methods; D003442:Crowns; D004955:Esthetics, Dental; D005881:Gingiva; D006801:Humans; D013053:Spectrophotometry / Q000295:instrumentation