Objective: To examine the effects of six whitening mouthwashes on tooth color and immediate bond strength to the enamel.
Materials and methods: Human incisors were divided into seven groups (n = 10) according to mouthwashes (R.O.C.S Black Edition White, Splat White Plus, Colgate Plax White Charcoal, Signal White Now, Listerine Advanced White, Colgate Optic White, and distilled water). After the initial color measurements, the teeth were exposed to mouthwash for 4 weeks. Then, the color measurements were repeated. Then, cylindrical composite resin blocks were immediately applied to the enamel surfaces and subjected to shear bond strength tests. Data were analyzed using Kruskal-Wallis and Bonferroni tests (α = 0.05).
Results: Δ𝑏, Δ𝐿, and ΔE00 values did not present significant differences among the groups. Significant differences among the groups were determined for Δ𝑎 and ΔWID values (p < 0.05). R.O.C.S Black Edition White and Splat White Plus produced clinically acceptable color changes. Signal White Now, Splat White Plus, and Listerine Advanced White created acceptable whiteness changes. The mouthwashes did not statistically affect the bond strength compared to the distilled water (p > 0.05).
Conclusions: Whitening mouthwash containing blue covarine revealed more acceptable color and whitening changes. Mouthwash containing charcoal led to the lowest enamel bond strength values.
Clinical significance: The content of whitening mouthwashes affected the degree of tooth whitening and shear bond strength to enamel.