Method: Sixty bovine teeth had their roots cut and buccal enamel polished. The specimens were divided into 5 groups, and they all suffered demineralization (artificial caries), except G1 (sound enamel). G2 received no remineralizing treatment. G3 to G5 received different remineralizing treatments: G3- immersion in artificial saliva for 8 weeks, G4- daily soaking for 1 min in a 0.05% sodium fluoride solution for 8 weeks, G5- infiltration with resin material Icon (DGM, Hamburg, Germany). This was followed by restorative treatment in all specimens: application of the one-step self-etching adhesive system Adper Easy One (3M-ESPE, USA) and composite resin Filtek Z350XT (3M-ESPE, USA), according to the manufacturer’s instructions. Artificial aging was performed with thermomechanical cycling machine. The teeth were sectioned into 0.9x0.9mm sticks and stressed to failure using a universal testing machine at cross-head speed of 1mm/min. Remaining teeth in each group were used for Scanning Electron Microscopy.
Result: Data were subjected to one-way ANOVA, which showed significant differences among groups for µTBS (p<0.05). Tukey test’s results (mean ± SD; in MPa) were: G1 (30.37 ± 6.96)a; G2 (14.62 ± 4.47)b; G3 (9.79 ± 2.32)b; G4 (9.36 ± 2.31)b; G5 (30.78 ± 8.68)a.
Conclusion: Resin bonded to demineralized enamel remineralized by an infiltrant (Icon) and resin bonded to sound enamel showed similar µTBS values, and both were significantly higher than resin bonded to demineralized enamel remineralized by saliva or sodium fluoride.