title: Computerized color formulation for African-Canadian people requiring facial prostheses: a pilot study.
abstract: OBJECTIVE
  The aim of this study was to investigate the effectiveness of spectrophotometry and a computerized color formulation system to predict pigment formulas for color mixing silicone elastomer to match the skin color of African-Canadian people.
  
  
  METHODS
  In a prospective study, reflectance spectrophotometery was used to measure the skin color of 19 African-Canadian subjects. The spectral data for each subject was used in a computerized color formulation system to predict colorants required to mix silicone elastomer to match each subject's skin color. Delta-E values were recorded for each silicone sample in comparison to the subject's skin measurement. An analysis of variance was used to determine significance among variables, and a Tukey HSD post hoc test was used to assess paired comparisons.
  
  
  RESULTS
  Delta-E decreased with iterative mixes of colored silicone for each subject, and pigment loading increased with iterative mixes. Delta-E values for the third iterative mix (fourth and final sample) ranged between 1.49 and 8.82.
  
  
  CONCLUSIONS
  Spectrophotometry and computerized color formulation provide a foundation in the color matching procedure for facial prostheses that offers objectivity to an otherwise subjective task. Through further study of spectrophotometry and computerized color formulation, and with the development of pigment databases appropriate for the African-Canadian population, it may be possible to establish a precise and repeatable color matching system that predicts required colorants and controls metamerism.
authors.affiliation: Department of Fixed & Removable Prosthodontics, Guy's, King's & St. Thomas' School of Dentistry, King's College, London, UK. trevor.coward@kcl.ac.uk
authors.forename: T J
authors.initials: TJ
authors.lastname: Coward
authors.forename: R
authors.initials: R
authors.lastname: Seelaus
authors.forename: S Y
authors.initials: SY
authors.lastname: Li
mesh_terms: D044383:Black People; D002170:Canada; D004396:Coloring Agents / Q000737:chemistry; D017076:Computer-Aided Design; D019992:Databases as Topic; D005145:Face; D006801:Humans; D010865:Pilot Projects; D011446:Prospective Studies; D017797:Prosthesis Coloring; D011474:Prosthesis Design; D012826:Silicone Elastomers / Q000737:chemistry; D012880:Skin Pigmentation; D012984:Software; D013053:Spectrophotometry
chemical_list: D004396:Coloring Agents; D012826:Silicone Elastomers