title: Comparison of bleaching efficacy of two bleaching agents on teeth discoloured by different antibiotic combinations used in revascularization.
abstract: OBJECTIVE
  To investigate the whitening effects of different bleaching agents on teeth discoloured by different antibiotic combinations of ciprofloxacin and metronidazole with minocycline, doxycycline, amoxicillin or cefaclor.
  
  
  METHODS
  Forty extracted bovine incisors were collected and discoloured with triple antibiotic pastes (TAP) with minocycline, doxycycline, amoxicillin and cefaclor throughout 30 days. The specimens were then randomly divided into two subgroups and each group received different bleaching materials: 35% hydrogen peroxide and sodium perborate. Spectrophotometric measurements were obtained on the buccal surfaces of the crown, firstly in the beginning, then on the 4th, 8th and 12th days after the placement of the bleaching materials. The acceptability threshold was set to 3.5. The ∆E values were calculated and the data was analysed using the repeated measures analysis of variance (P = .05).
  
  
  RESULTS
  All the test groups induced colour changes exceeding the acceptability threshold 30 days after the antibiotic pastes were placed. The 35% hydrogen peroxide was more effective than sodium perborate in the whitening of discoloured teeth by antibiotic pastes (P = .001). The whitening effect after the 8th and 12th days was significantly more than after 4 days of treatment (P <.001). The discolouration caused by the TAP with minocycline and cefaclor showed greater whitening compared to the TAP with doxycycline and amoxicillin groups (P <.05).
  
  
  CONCLUSIONS
  The whitening treatment effect of 35% hydrogen peroxide on teeth discoloured by antibiotic pastes seems to have significantly outperformed the sodium perborate treatment. Both bleaching agents were allowed to bleach the teeth gradually each day and the effects on the 8th and 12th days were superior to the one on the 4th day.
  
  
  CONCLUSIONS
  The use of 35% hydrogen peroxide could be advantageous to bleach the teeth discoloured with antibiotic pastes compared to sodium perborate.
authors.affiliation: Department of Restorative Dentistry, Faculty of Dentistry, Izmir Katip Celebi University, Izmir, Turkey.
authors.forename: Bilal
authors.initials: B
authors.lastname: Yasa
authors.forename: Hakan
authors.initials: H
authors.lastname: Arslan
authors.forename: Merve
authors.initials: M
authors.lastname: Akcay
authors.forename: Fevzi
authors.initials: F
authors.lastname: Kavrik
authors.forename: Huseyin
authors.initials: H
authors.lastname: Hatirli
authors.forename: Bulent
authors.initials: B
authors.lastname: Ozkan
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D057886:Bleaching Agents / Q000008:administration & dosage*; D001881:Borates / Q000008:administration & dosage; D002417:Cattle; D003188:Composite Resins; D006861:Hydrogen Peroxide / Q000008:administration & dosage*; D066298:In Vitro Techniques; D000068897:Iridescence; D014073:Tooth Bleaching / Q000379:methods*; D014075:Tooth Discoloration / Q000139:chemically induced* / Q000188:drug therapy*
chemical_list: D000900:Anti-Bacterial Agents; D057886:Bleaching Agents; D001881:Borates; D003188:Composite Resins; C000621148:Filtek Ultimate Flowable; D006861:Hydrogen Peroxide; C027707:sodium perborate