Prior Application of 10% Potassium Nitrate to Reduce Postbleaching Sensitivity: A Randomized Triple-Blind Clinical Trial

• Published in: The journal of evidence-based dental practice 2020-06, Vol.20 (2), p.101406-101406, Article 101406
• Main Authors: Rezende, Márcia, da Silva, Karine Leticia, Miguel, Thais Caroline, Farago, Paulo Vitor, Loguercio, Alessandro Dourado, Martins, Luciana Dorochenko, Reis, Alessandra
• Format: Article
• Language: English
• Subjects: Dental bleaching; Dentin sensitivity; Dentistry; Hydrogen peroxide; Randomized controlled trial
• ISSN: 1532-3382; 1532-3390
• DOI: 10.1016/j.jebdp.2020.101406

To evaluate if the topical application of 10% potassium nitrate applied before in-office bleaching is effective to reduce the risk and intensity of tooth sensitivity (TS), as well as to evaluate if its application can jeopardize color change. A randomized, split-mouth triple-blind clinical trial was conducted on 43 young patients with incisors A2 or darker. Half of the patient's upper arch received either the application of a 10% potassium nitrate or placebo gel for 10 min in a university setting. In-office bleaching was performed in three 15-min applications in two clinical sessions (1-week interval) using 35% hydrogen peroxide. Risk and intensity of TS was recorded with a 0-4 Numeric Rating Scale and a 0-10 Visual Analogue Scale during bleaching, 1 hour, 24 hours, and 48 hours after bleaching. Color was evaluated before and 1 month after bleaching with shade guides (Vita Classical and Vita Bleachedguide) and a spectrophotometer. The risk of TS (McNemar's test) and intensity of TS (Wilcoxon signed-rank for Numeric Rating Scale and paired t-test for Visual Analogue Scale) were statistically evaluated. Color change was compared using paired t-test. Significant level was set at 5%. No significant difference was observed in the absolute risks of TS between groups (RR = 1.11; 95% CI 0.97 to 1.27; P = .12), which exceeded 87% for both groups. Similarly, no difference in TS intensities was detected (P > .05). Significant whitening was observed with all color measurement instruments with no difference between groups (P > .05). The topical application of 10% potassium nitrate, before in-office bleaching, did not reduce the risk and intensity of TS and did not jeopardize color change.