Chromatic analysis of teeth exposed to different mouthrinses.

OBJECTIVES: The aim of this study was to assess, in vitro, the color of teeth exposed to different mouthrinses for a prolonged period. METHODS: Bovine teeth were distributed in four groups: control, alcohol-containing mouthrinse (Listerine(®)), alcohol-free mouthrinse (Oral-B(®)) and chlorhexidine mouthrinse (Periogard(®)). The teeth were submitted to two cycles of staining and artificial aging. Color evaluation was performed with a digital spectrophotometer at the beginning of the experiment and after every cycle. Color changes were characterised using the system defined by the Comission Internationale de L'Eclairage (CIE L*, a*, b*). Data were analysed using the ANOVA and Tukey's post hoc test. RESULTS: After the two cycles of staining and artificial aging, ΔE, ΔL and Δb from the alcohol-containing mouthrinse showed statistically significant differences when compared to the other groups. The ΔE values of the Listerine(®) group after the two cycles were greater than 3.7, indicating a visually perceptible color change. CONCLUSIONS: The teeth exposed to the alcohol-containing mouthwash Listerine(®) were the only ones that presented a clinically perceptible color change. CLINICAL SIGNIFICANCE STATEMENT: A blue-colored alcohol-containing mouthwash was shown to be capable of causing dental color change after a prolonged period of exposure. Special care must be taken when choosing and prescribing the prolonged use of the same mouthwash.

Color stability and fluorescence of different orthodontic esthetic archwires.

OBJECTIVE: To evaluate the color stability of six esthetic archwires at different time periods and their fluorescence. MATERIALS AND METHODS: Samples were evaluated after 7, 14, and 21 days of immersion in staining solution. Color measurements were performed by means of a spectrophotometer according to the Commission Internationale de I'Eclairage L*a*b* system, and color changes (ΔE*) and National Bureau of Standards units were computed. The fluorescence of as-received samples was evaluated by two observers and compared with that of a bovine central incisor. Statistical differences were investigated using analysis of variance and Tukey's post hoc test. RESULTS: All brands showed statistically significant color change after 21 days (ΔE* from 1.88 to 12.06). The Optis archwire (fiber-reinforced composite) presented the highest color alteration, although staining was observed only near its ends. The Trianeiro archwire (coated nickel-titanium) and the Ortho Organizers archwire (coated stainless steel) presented with less color change. The Optis archwire was the only one that presented with fluorescence similar to that of bovine teeth. CONCLUSIONS: All esthetic archwires assessed showed clinically noticeable color change after 21 days in staining solution. The optical properties of currently available esthetic archwires may not yet be ideal.