Peroxide penetration from the pulp chamber to the external root surface after internal bleaching

Am J Dent. 2010 Jun;23(3):171-4.

Abstract

Purpose: To quantify the amount of peroxide penetration from the pulp chamber to the external surface of teeth during the walking bleaching technique.

Methods: Seventy-two bovine lateral incisors were randomly divided over five experimental groups and one control (n = 12 per group): (1) 35% hydrogen peroxide (HP); (2) 35% carbamide peroxide (CP); (3) sodium perborate (SP); (4) (HP+SP); (5) (CP+SP) and (6) Control (CG), deionized water. All groups were treated according to the walking bleach technique. After 7 days at 37 degrees C in an acetate buffer solution, 100 microl violet leukocrystal coloring and 50 microl peroxidase was added, producing a blue stain that could be measured in a spectrophotometer and then converted into peroxide microg/ml.

Results: G5 exhibited the greatest penetration, while G2 and G3 produced the lowest values. All bleaching agents penetrated from the pulp chamber to the external root surface. There was a direct correlation between the presence of oxidative agents and penetration potential. Sodium perborate in distilled water was less oxidative and appeared to be the least aggressive bleaching agent.

Publication types

  • Comparative Study

MeSH terms

  • Acid Etching, Dental
  • Animals
  • Borates / administration & dosage
  • Borates / pharmacokinetics*
  • Carbamide Peroxide
  • Cattle
  • Dental Cementum / metabolism
  • Dental Enamel Permeability
  • Dentin Permeability
  • Dose-Response Relationship, Drug
  • Drug Combinations
  • Hydrogen Peroxide / administration & dosage
  • Hydrogen Peroxide / pharmacokinetics*
  • Oxidants / pharmacology*
  • Oxidation-Reduction
  • Peroxides / administration & dosage
  • Peroxides / pharmacokinetics*
  • Random Allocation
  • Tooth Bleaching / methods*
  • Tooth Cervix / metabolism*
  • Tooth, Nonvital
  • Urea / administration & dosage
  • Urea / analogs & derivatives*
  • Urea / pharmacokinetics

Substances

  • Borates
  • Drug Combinations
  • Oxidants
  • Peroxides
  • Carbamide Peroxide
  • Urea
  • Hydrogen Peroxide
  • sodium perborate