Edition V16N02 | Year 2019 | Editorial Artigo Inédito | Pages 54 to 68
This study evaluated the repair bond strength (RBS), contact angle (θ) and surface morphology of composite resin repairs on dentin (DE), composite resin (CR) and dentin-composite resin interface (DE-CR), after different surface treatments. Bovine incisors were used for RBS and θ tests; CR blocks (Opallis, FGM, Brazil) were prepared for θ evaluation with water. All samples were separated into four groups (n=10 for RBS; n=5 for θ), according to the bonding agent applied: no surface treatment (C); acid-etching followed by adhesive application (Ac+Ad); silane (S); and acid-etching + silane + adhesive (Ac+S+Ad). For RBS test, the microshear bond strength test was carried out. For θ test, the samples were evaluated by dropping water onto their surface after treatment with the bonding agents. All tested substrates were analyzed using scanning electron microscopy (SEM), and data were analyzed with ANOVA and Student-Newman-Keuls test (α = 0.05). In DE, the application of Ac+S+Ad reduced dentin wettability. In CR, all bonding agents increased wettability, compared with C. For RBS, a significantly higher repair bond strength was observed for groups treated with adhesive, compared with C and S groups, at both DE and DE-CR interface. In CR, only C showed lower bond strength values, compared with the others. In conclusion, dental practitioners should be aware that the repair bonding performance of composite restorations may depend on the substrates involved in the repairing procedure, with the application of adhesive system being the most advisable chemical treatment for obtaining proper bonding to all substrates.
Manso IS, Valente LL, Münchow EA, Isolan CP, Lima FG, Moraes RR. Bonding to composite resin, dentin, and composite-dentin interface, regarding restoration repair. J Clin Dent Res. 2019 May-Aug;16(2):54-68. DOI: https://doi.org/10.14436/2447-911x.16.2.054-068.oar