title: Effect of home bleaching and smoking on marginal gingival epithelium proliferation: a histologic study in women.
abstract: BACKGROUND
  Animal studies have suggested that home bleaching agents can cause morphological alterations and changes in the proliferative rate of oral epithelium.
  
  
  METHODS
  A bleaching agent containing 10% carbamide peroxide with carbopol was used in 11 women (five smokers and six non-smokers) during a 5-week period. Two biopsies were performed, one of them 15 days before the beginning of the home bleaching treatment and the other immediately after the 5-week bleaching treatment. Two analyses were performed in the histological sections obtained from the biopsies: epithelium morphometry and assessment of the epithelium's proliferative activity by proliferating cell nuclear antigen (PCNA) immunohistochemistry.
  
  
  RESULTS
  The home bleaching agent increases epithelium thickness and the PCNA index in both smoker and non-smoker patients.
  
  
  CONCLUSIONS
  Carbamide peroxide (10%) caused an augmentation in the proliferative activity within the basal and parabasal layers of the gingival epithelium, resulting in a change in this tissue's morphometry.
authors.affiliation: Professor of Periodontology, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Brazil. Periodontia@rocketmail.com
authors.forename: Luiz Cesar
authors.initials: LC
authors.lastname: da Costa Filho
authors.forename: Carolina Covolo
authors.initials: CC
authors.lastname: da Costa
authors.forename: Marina Lara
authors.initials: ML
authors.lastname: Sória
authors.forename: Rumio
authors.initials: R
authors.lastname: Taga
mesh_terms: D000180:Acrylic Resins; D000328:Adult; D001706:Biopsy; D000077463:Carbamide Peroxide; D002455:Cell Division / Q000187:drug effects; D004396:Coloring Agents; D003238:Connective Tissue / Q000187:drug effects / Q000473:pathology; D003773:Dental Plaque / Q000517:prevention & control; D004338:Drug Combinations; D004847:Epithelial Cells / Q000187:drug effects / Q000473:pathology; D004848:Epithelium / Q000187:drug effects / Q000473:pathology; D005260:Female; D005456:Fluorescent Dyes; D005500:Follow-Up Studies; D005881:Gingiva / Q000187:drug effects / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D016555:Matched-Pair Analysis; D009910:Oral Hygiene; D016877:Oxidants / Q000627:therapeutic use*; D010545:Peroxides / Q000627:therapeutic use; D011145:Polyvinyls / Q000627:therapeutic use; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D012907:Smoking; D013223:Statistics as Topic; D014073:Tooth Bleaching; D014508:Urea / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D000180:Acrylic Resins; D004396:Coloring Agents; D004338:Drug Combinations; D005456:Fluorescent Dyes; D016877:Oxidants; D010545:Peroxides; D011145:Polyvinyls; D018809:Proliferating Cell Nuclear Antigen; C006912:carboxypolymethylene; D000077463:Carbamide Peroxide; D014508:Urea