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Influence of tooth sensitivity on shortening the interval between in-office bleaching sessions with acidic pH gel: A
Sarah Arruda Gonçalves Ferraz da Costa1, Carolina da Costa Ferreira Silva1, Tâmmile Vallentine Soares Amado1
1School of Dentistry, Federal Fluminense University, Nova Friburgo, Rio de Janeiro, Brazil.
Background:
This randomized clinical trial evaluated the intensity and risk of developing tooth sensitivity (TS) when in-office bleaching with an acidic pH gel was performed at 2-day or 7-day intervals between sessions. In addition, bleaching efficacy was assessed for both protocols.
Methods:
Forty-seven participants were randomized into 2 parallel groups and received 2 in-office bleaching sessions using an acidic 35% hydrogen peroxide gel at either a 2-day or 7-day interval. TS intensity was recorded 1 hour, 24 hours, and 48 hours after each session using a visual analog scale ranging from 0 through 10 cm in which 0 means no tooth sensitivity and 10 cm means worst imaginable tooth sensitivity. Color was measured at baseline and 1-month posttreatment with the VITA Classical (VITA Zahnfabrik) and VITA Bleachedguide 3D-MASTER shade guides (VITA Zahnfabrik) as well as a digital spectrophotometer. Treatment duration, TS intensity, and color change were analyzed using independent sample t tests and absolute risk of TS was compared using Fisher exact test (α = .05).
Results:
The total treatment duration differed significantly between the 2-day and 7-day protocols (P < .001). No significant differences were found between the groups in terms of the worst TS intensity score or risk (relative risk, 1.0; 95% CI, 0.8 to 1.2; P > .30). Both protocols achieved significant and clinically perceptible bleaching, with no differences in color change between groups according to assessments (P > .23).
Conclusions:
Shortening the interval between in-office bleaching sessions with an acidic pH gel from 7 days to 2 days did not increase the intensity or risk of developing TS nor did it compromise bleaching efficacy.
Practical Implications:
Reducing the interval between in-office bleaching sessions with an acidic pH hydrogen peroxide gel may safely accelerate treatment completion without increasing TS or affecting bleaching outcomes, optimizing chair time. This clinical trial was registered at ClinicalTrials.gov. The registration number is NCT06394557.