title: A novel evaluation method for optical integration of class IV composite restorations.
abstract: BACKGROUND
  This aim of this study was to compare traditional visual appreciation with spectrophotometry to evaluate the optical integration of anterior composite restorations.
  
  
  METHODS
  Eleven restorations were evaluated in eight patients receiving dental treatment at fourth and fifth year student clinics at the dental school of the University of Geneva, Switzerland. Colour integration of completed restorations was assessed by visual observation according to USPHS criteria and spectrophotometric analysis; both methods were then compared.
  
  
  RESULTS
  A mean ΔE of 1.1 (range 0.7 to 1.7) corresponded to an optimal visual integration between natural tooth and restoration (alpha score) while a mean ΔE of 3.3 (range 2.6 to 3.8) corresponded to clinically 'non-acceptable' visual integration (charlie score). Restorations scored as 'bravo', corresponded to a suboptimal but not disturbing visual integration, had a mean ΔE of 2. L* and b* values present at the bevel area and into the composite bulk tended to be lower than that of the natural tooth while a* composite values were slightly higher.
  
  
  CONCLUSIONS
  The spectrophotometric method employed in this pilot study has confirmed the published range of ΔE (global difference of L*a*b* values) corresponding to clinically 'optimal', 'acceptable' and 'unacceptable' colour integration.
authors.affiliation: Department of Cariology and Endodontics, School of Dentistry, University of Geneva, Switzerland.
authors.forename: D
authors.initials: D
authors.lastname: Dietschi
authors.forename: M
authors.initials: M
authors.lastname: Abdelaziz
authors.forename: I
authors.initials: I
authors.lastname: Krejci
authors.forename: E
authors.initials: E
authors.lastname: Di Bella
authors.forename: S
authors.initials: S
authors.lastname: Ardu
mesh_terms: D000293:Adolescent; D003116:Color; D003124:Colorimetry / Q000379:methods; D003188:Composite Resins; D003793:Dental Restoration, Permanent; D004955:Esthetics, Dental; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D013053:Spectrophotometry / Q000379:methods; D013557:Switzerland; D055815:Young Adult
chemical_list: D003188:Composite Resins