Effect of bleaching protocols with 38% hydrogen peroxide and post-bleaching times on dentin bond strength

Braz Dent J. 2011;22(4):317-21. doi: 10.1590/s0103-64402011000400010.

Abstract

This study assessed the effect of bleaching protocols with 38% hydrogen peroxide (HP) and post-bleaching times on shear bond strength of a composite resin to dentin. One-hundred slabs of intracoronary dentin were included and randomly assigned into 2 groups according to the bleaching protocol: HP (2 applications of 10 min each) and HP activated by LED laser (2 applications of 10 min each/45 s of light activation). Groups were subdivided according to the post-bleaching time (n=10): 1 day, 3 days, 7 days, 10 days and 14 days. The control group was unbleached and restored (n=10). The specimens were restored with Single Bond adhesive system/Filtek Z250 resin using a polytetrafluorethylene matrix and were submitted to the shear bond strength testa after 24 h,. Data were analyzed by ANOVA and Tukey's test (α=0.05). Unbleached group (0.283 ± 0.134) had the highest bond strength and was statistically similar (p>0.05) to HP/10 days (0.278 ± 0.064), HP + LED laser/10 days (0.280 ± 0.078), HP/14 days (0.281 ± 0.104), HP + LED laser/14 days (0.277 ± 0.093). Lower bond strength were verified in HP/1 day (0.082 ± 0.012), HP/3 days (0.079 ± 0.013), HP + LED laser/1 day (0.073 ± 0.018) and HP + LED laser/3 days (0.080 ± 0.015), which were statistically similar (p>0.05). HP/7 days (0.184 ± 0.154) and HP + LED laser/7 days (0.169 ± 0.102) had intermediate values (p<0.05). The restorative procedure of intracoronary dentin bleached with 38% HP with or without the use of light source should be performed after at least 10 days after the bleaching treatment.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Acid Etching, Dental / methods
  • Bisphenol A-Glycidyl Methacrylate / chemistry
  • Composite Resins / chemistry
  • Dental Bonding*
  • Dental Stress Analysis / instrumentation
  • Dentin / ultrastructure*
  • Dentin-Bonding Agents / chemistry
  • Humans
  • Hydrogen Peroxide / chemistry*
  • Lasers, Semiconductor
  • Materials Testing
  • Oxidants / chemistry*
  • Phosphoric Acids / chemistry
  • Shear Strength
  • Stress, Mechanical
  • Time Factors
  • Tooth Bleaching / methods
  • Tooth Bleaching Agents / chemistry*

Substances

  • Composite Resins
  • Dentin-Bonding Agents
  • Filtek Z250
  • Oxidants
  • Phosphoric Acids
  • Tooth Bleaching Agents
  • single bond
  • Bisphenol A-Glycidyl Methacrylate
  • Hydrogen Peroxide
  • phosphoric acid