Desensibilizing-containing in-office Bleaching Gel: A Triple-blind Clinical Trial on Sensitivity

Objectives: To reduce bleaching-induced tooth sensitivity (TS) of in-office bleaching, desensitizing agents can be incorporated to bleaching gels. This randomized clinical trial (RCT) evaluated the risk and intensity of tooth sensitivity (TS) and color change after in-office bleaching with a desensitizing-containing (5% potassium nitrate) and desensitizing-free 35% hydrogen peroxide (HP) gel (Whitening HP AutoMixx, FGM).
Methods: A triple-blind, split-mouth RCT was conducted on 60 caries-free adult patients. Two bleaching sessions with 35% HP gel were performed with one-week interval. The absolute risk and intensity of TS were assessed by visual analogue scale (VAS) and numerical rating scale (NRS) up to 48 h after each session. Color change was recorded using shade guides (Vita Classical and Vita Bleachedguide) and the Easyshade spectrophotometer at baseline and 30 days after bleaching. The risk and intensity of TS were evaluated by the McNemar and the Wilcoxon Signed Rank tests, respectively. Color change (ΔSGU and ΔE) were evaluated by Mann-Whitney test and paired t-test, respectively (α = 0.05).
Results: No difference in the absolute risk of TS was observed (OR = 0.5; 95% CI 0.0 to 9.6; p = 1.0). However lower pain intensity was observed for the desensitizing-containing gel compared to the control gel during bleaching (p = 0.003), up to 1 h (p = 0.002) and up to 24 h (p = 0.01) with a mean difference of 1.5 ± 3.6 (95% CI 0.6 - 2.5) in VAS units in the period of up to 1 h and of 1.2 ± 3.1 (0.4 - 2.0) in the period of up to 24 h.


Conclusions: The incorporation of potassium nitrate in in-office bleaching gels does not reduce the risk of TS and does not affect color change but it reduces the intensity of TS during and after bleaching.