Avaliação da resistência de união da interface resina/dentina após aplicação de agente remineralizante à base de CPP-ACP

Abstract

Direct restorations on affected dentin are more susceptible to degradation, and adhesion may be impaired. In this sense, biomimetic remineralization brought resources that alleviate this problem, thanks to bioactive agents that reproduce the natural remineralization process, such as the casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), which displaces calcium and phosphate ions to the zone of demineralization, inhibiting it. The objective of this work was to evaluate the bond strength at the interface composite resin - demineralized dentin treated with remineralizing paste based on CPP-ACP. Thirty-two healthy third molars were used, which had the roots and crown enamel removed, randomly divided into 4 groups (n=8): G1: (DH) – Sound dentin; G2: (DH/CPP-ACP) – Sound dentin treated with CPP-ACP; G3: (DD)- Demineralized dentin; G4: (DD/CPP-ACP) – Demineralized dentin treated with CPP-ACP. The chemical medium applied to simulate demineralization was a 0.1M lactic acid solution, titrated to pH 5.0, for 48h. The specimens were restored with universal adhesive system in the self-ecthing protocol and, after 24 hours, toothpicks and subjected to the microtensile strength test. The values obtained were submitted to two-way ANOVA (p<0.05). Statistical analysis showed no significant interaction between the evaluated factors: type of dentin and use of remineralizing agent (p=0.31). The mean and standard deviation values were: G1: 22.90 (±7.22); G2: 31.40 (±6.83); G3: 28.4 (±12); G4: 32.2 (±15.4). The demineralization medium did not negatively affect the bonding interface and the use of the remineralizing agent did not prove to be advantageous in the appreciated scenario.