Influence of surface treatment on the fluorescence of composite resins subjected to in situ bleaching

Objective Use fluorescence analysis to evaluate the effect of polishing and surface sealant on the color of composite resin bleached with carbamide peroxide and subjected to staining. Materials and methods Forty-eight composite resin specimens (Z250/Z350XT) were fabricated. After 24 hours stored in distilled water, all specimens were submitted to in situ bleaching with 16% home peroxide for 8 hours daily for a period of 14 days. Subsequently specimens were separated in three groups according to surface treatment proposed (group 1-polishing Sof-Lex; group 2-BisCover; group 3-control). After this, all the specimens were stained with red wine. A spectrofluorometer was used to evaluate the fluorescence in two readouts (L0-after surface treatment and L1-after staining).Data were analyzed by applying ANOVA using a statistical software program. Results No differences were shown for the factor treatment and other interactions. The lowest mean fluorescence value was found for Z350XT resin (1759.18 +/- 0.13) when compared with Z250 (6863.92 +/- 0.13). There was significant difference in the mean fluorescence values for all surface treatments between the two different readouts L0 (4820.93 +/- 0.05) and L1 (3802.17 +/- 0.05). Conclusion The results suggested that all surface treatments proposed did not influenced the results of wine staining of bleached resins when compared with the control evaluated by the fluorescence method. Clinical significance The purposes of this research was to find solutions, by means of surfaces treatment, to achieve restorations with a satisfactory and similar final aspect in relation to the teeth, and avoid discrepancies related to the esthetics and longevity of the restoration.