Methods: Nanocomposite disks (1.5mm x 9.2mm) were prepared for each of the two nanocomposites: Filtek Supreme Plus, Shade A2 (3M ESPE, St Paul, MN) and Simile, Shade A2 (Pentron, Wallingford, CT). The baseline color of the disks was measured using a spectrophotometer (Color Eye 7000, GretagMacbeth, Grand Rapids, MI). Five of each type of nanocomposite disks were coated with one of the three types of fluoride varnishes: Vanish 5% Na F (Omnii, A 3M ESPE, St Paul, MN), Duraflor 5% NaF (Medicom, Lachine, Québec, Canada) and Fluor-Protector 0.1% difluorosilane (Ivoclar Vivadent, Liechtenstein). The color of the samples was measured after 2 hours using a spectrophotometer (Color Eye 7000), and again after 4 hours in artificial saliva followed by a single cycle of tooth brushing (V8). The specimens were placed in the tooth brushing machine (V8) for 192 cycles, equivalent to one week of brushing. The data was analyzed with Analysis of Variance statistics (P values).
Results: The Vanish group showed an increase in its L-value, giving the composite an immediate lighter and whiter appearance (P value). Duraflor showed an immediate and unacceptable color change in both groups, especially in the Simile group (P value). Fluor-Protector only showed a slight unacceptable color change in the Filtek group; however, immediate acceptable results were accomplished in the Simile/Fluor-Protector group (P value).
Conclusion: Vanish will produce an immediate whiter appearance and therefore, may be indicated in patients with anterior composite restorations. All the nanocomposites returned to their original color after one week of brushing.