Dentin bond strength of a fluoride-releasing adhesive system submitted to pH-cycling

Braz Dent J. 2014 Nov-Dec;25(6):472-8. doi: 10.1590/0103-6440201302445.

Abstract

To evaluate the microtensile bond strength (µTBS) of a fluoride-containing adhesive system submitted to a pH-cycling and storage time regimen for primary outcomes. As secondary outcomes the fluoride released amount was evaluated. Twelve dentin surfaces from sound third molar were divided into 2 groups according to adhesive systems: Clearfil SE Protect (PB) and Clearfil SE Bond (SE). Sticks obtained (1.0 mm2) from teeth were randomly divided into 3 subgroups according to storage regimen model: immediate (24h); 5-month deionized water (W); and pH-cycling model (C). All sticks were tested for µTBS in a universal testing machine. Fluoride concentration was obtained from 1-4 days and 30-day in W and 1-4 days in demineralization (DE)/remineralization (RE) solutions from C, using a fluoride-specific electrode. µTBS and fluoride released data were, respectively, submitted to ANOVA in a split plot design and Tukey, and Friedman' tests (a=0.05). There was no significant interaction between adhesive system and storage regimen for µTBS. W showed the lowest µTBS values. There was no significant difference between 24 h and C models for µTBS. There was no significant difference between adhesive systems. Failure mode was predominantly cohesive within composite for the 24 h and W, for the C group it was mixed for SE and cohesive within composite for PB adhesive system. Fluoride concentrations in the DE/RE solutions were less than 0.03125 ppm and not detected in W. In conclusion, the fluoride-containing adhesive system performed similarly to the regular one. Hydrolytic degradation is the main problem with both adhesive systems, regardless of fluoride contents.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Dental Stress Analysis
  • Dentin-Bonding Agents / chemistry*
  • Fluorides / chemistry*
  • Hydrogen-Ion Concentration
  • Molar, Third
  • Random Allocation
  • Resin Cements / chemistry*
  • Self-Curing of Dental Resins
  • Tensile Strength

Substances

  • Clearfil Protect Bond
  • Clearfil SE Bond
  • Dentin-Bonding Agents
  • Resin Cements
  • Fluorides