Objective: To evaluate the effect of EDTA pre-treatment of dentine on resistance to degradation of the bond between dentine and resin-modified glass-ionomer cements.
Methods: Sixty non-carious human molars underwent cavity preparations. Teeth were restored with Fuji II LC or Vitremer. Half of the cavities were restored following manufacturers' instructions whereas the other half was pre-treated with EDTA (0.1M, pH 7.4) for 60s. Teeth were stored in water at 37 degrees C for 24h, 3 months or submitted to 10% NaOCl immersion for 5h. Teeth were sectioned into beams (1+/-0.1mm) and tested to failure in tension at 0.5mm/min. Bond strength data (MPa) were analyzed by ANOVA and SNK multiple-comparisons tests (p<0.05).
Results: When EDTA was used for pre-treatment of dentine, higher bond strengths were observed for both cements. Degradation challenges produced a decrease in bond strength values only in the Vitremer group. This decrease was avoided when EDTA was used for dentine treatment before restoring with Vitremer.
Conclusions: EDTA pre-treatment of dentine increases bond strength of resin modified glass-ionomers cements to dentine and improves resistance to degradation of the bond between Vitremer and dentine.