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Comparative Clinical Study of Two Tooth-Whitening Protocols: A Randomized Clinical Trial. Part 2
Abstract:
This study clinically evaluated the efficacy of two different home tooth-whitening protocols to determine which one is more effective by applying the whitening gel every 48 hours or every 72 hours for 6 weeks. The differences in tooth sensitivity were also analyzed. A sample of 72 patients were randomly divided into four groups: In group A (n = 24), 16% carbamide peroxide (Pola Night, SDI Limited) was applied every 48 hours for 6 weeks; in group B (n = 24), 16% carbamide peroxide was applied every 72 hours for 6 weeks; in group C (control; n = 12), a placebo gel without peroxide (glycerin gel) was applied every 48 hours for 6 weeks; and in group D (control; n = 12), a placebo gel without peroxide (glycerin gel) was applied every 72 hours for 6 weeks. To compare the groups, color measurements were made using a spectrophotometer. For statistical analysis, ANOVA with Bonferroni test was used. The confidence interval (CI) was set at 95% (P ≤ .05). No statistically significant differences were found between applying 16% carbamide peroxide every 48 hours and every 72 hours for 6 weeks (P > .05). The study concluded that 16% carbamide peroxide was equally effective when applied using both protocols.
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