title: A randomized CIE L*a*b* evaluation of external bleaching therapy effects on fluorotic enamel stains.
abstract: OBJECTIVE
  To evaluate the effect of external bleaching on the color and luminosity of fluorotic stains and adjacent, normally mineralized enamel areas by means of CIE L*a*b* colorimetry.
  
  
  METHODS
  Eighteen adolescents with mild to moderate fluorotic stains were randomly assigned to either bleaching group A (n = 9) or control group B. Eligibility criteria were fluorotic stained maxillary incisors or canines and the informed consent of the participants and their guardians. Using a colorimeter, CIE L*a*b* values of maxillary incisors and canines were assessed at baseline (T1) in the center of the fluorotic stained area (F1) and at adjacent, normally mineralized enamel areas (F2). Then, external bleaching with Illumine office (30% hydrogen peroxide, Dentsply DeTrey) was performed for 60 minutes, followed by color reassessment (T2). After 14 days (T3), a 2-week home bleaching period with a daily bleaching time of 1 hour with Illumine home (15% carbamide peroxide, Dentsply DeTrey) was conducted with subsequent color determination (T4).
  
  
  RESULTS
  After completion of bleaching therapy, 96.0% of all fluorotic areas (F1) and 100% of normal enamel areas (F2) showed a significant change within group A, compared to 29.4% in control group B. Comparing the collective DeltaE (L*, a*, b*) of F1 and F2, 60.0% of all areas showed significant differences after completion of bleaching therapy, compared to 88.0% initially. Of group B sites, 82.4% showed color differences in the beginning (T1) and 88.2% at the end (T4).
  
  
  CONCLUSIONS
  Whereas a single 1-hour session of in-office bleaching with 30% hydrogen peroxide does not significantly affect the color and luminosity of fluorotic teeth, a 14-day period of home bleaching leads to an assimilation of the color of the fluorotic stain with the color of surrounding enamel areas due to different responses of sound and fluorotic enamel to the bleaching regime.
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Center of Dentistry, Georg-August University, Göttingen, Germany. mknoesel@yahoo.de
authors.forename: Michael
authors.initials: M
authors.lastname: Knösel
authors.forename: Rengin
authors.initials: R
authors.lastname: Attin
authors.forename: Klaus
authors.initials: K
authors.lastname: Becker
authors.forename: Thomas
authors.initials: T
authors.lastname: Attin
mesh_terms: D000293:Adolescent; D000077463:Carbamide Peroxide; D003124:Colorimetry; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D005260:Female; D009050:Fluorosis, Dental / Q000150:complications*; D006801:Humans; D006861:Hydrogen Peroxide / Q000008:administration & dosage*; D008297:Male; D016877:Oxidants / Q000008:administration & dosage*; D017060:Patient Satisfaction; D010545:Peroxides / Q000008:administration & dosage*; D011795:Surveys and Questionnaires; D014073:Tooth Bleaching / Q000379:methods*; D014075:Tooth Discoloration / Q000188:drug therapy* / Q000209:etiology; D014508:Urea / Q000008:administration & dosage / Q000031:analogs & derivatives*
chemical_list: D004338:Drug Combinations; D016877:Oxidants; D010545:Peroxides; D000077463:Carbamide Peroxide; D014508:Urea; D006861:Hydrogen Peroxide