EDTA treatment improves resin-dentin bonds' resistance to degradation

Abstract

The existence of unprotected collagen fibrils within the hybrid layer compromises the longevity of restorations. This phenomenon may be avoided if solutions other than strong acids are used for dentin demineralization. The hypothesis to be tested is that bond durability may be improved by EDTA demineralization. Dentin surfaces (human and bovine) were bonded: (1) after phosphoric-acid-etching, and after EDTA demineralization with (2) a total-etch adhesive and (3) a self-etching adhesive. After the teeth were sectioned into beams, half of the specimens were immersed in NaOCl, while the other half was immersed in water. Beams were tested to failure in tension. ANOVA and multiple-comparisons tests were used (P < 0.05). No differences in bond strength were found among the 3 bonding procedures, although bonds made to human molars were 43-61% higher than those to bovine incisors. After NaOCl immersion, only specimens subjected to EDTA demineralization maintained the initial bond strength. We conclude that the collagen network is better-preserved after EDTA demineralization.