Effectiveness of nano-calcium phosphate paste on sensitivity during and after bleaching: a randomized clinical trial.

Alessandro Dourado Loguercio,Jose Bauer,Daniel Rodrigo Herrera,Lidia Yileng Tay,Alessandra Reis

doi:10.1590/1807-3107bor-2015.vol29.0099

Abstract

The study aimed to evaluate the effectiveness of in-office bleaching and associated tooth sensitivity on application of nano-calcium phosphate paste as desensitizing agent. Bleaching was performed with 35% hydrogen peroxide gel in 40 patients who were randomly divided into placebo and nano-calcium phosphate paste groups. Bleaching efficacy (BE) was evaluated using a value-oriented Vita shade guide. Tooth sensitivity was recorded using a numeric rating scale (0-4) during bleaching and up to 48 h after each session. The primary outcome of absolute risk of tooth sensitivity was compared using the Fisher's exact test (α = 0.05). The intensity of tooth sensitivity and the efficacy of in-office bleaching were also statistically evaluated. No significant differences in absolute risk and intensity of tooth sensitivity were detected between the groups (p = 1.0 and p = 0.53, respectively). BE was also found to be similar between the groups (p = 0.67). Although the use of a nano-calcium phosphate paste associated with fluoride and potassium nitrate did not influence the whitening outcome, but it also did not reduce bleaching-induced tooth sensitivity.

Highlights

The clinical effectiveness of at-home and in-office bleaching under the supervision of a dentist has been extensively documented.[1]
While in-office bleaching uses high concentrations of active hydrogen peroxide, the at-home protocol uses a lower concentration of active hydrogen peroxide
Grobler et al.[14] hypothesized that the low sensitivity rate reported for an at-home bleaching gel was because of the presence of calcium phosphate, potassium nitrate, and fluoride in the gel composition

Summary

Introduction

The clinical effectiveness of at-home and in-office bleaching under the supervision of a dentist has been extensively documented.[1]. The incorporation of calcium phosphate salts in bleaching gels has been shown to prevent loss of minerals and reduce loss of enamel microhardness and bleaching-induced tooth sensitivity.[4,5] A low risk of tooth sensitivity was reported for a calcium-containing in-office bleaching product.[12,13] Recently, two clinical studies showed that the application of calcium phosphate paste was effective in reducing at-home bleaching-induced tooth sensitivity.[14,15] Grobler et al.[14] hypothesized that the low sensitivity rate reported for an at-home bleaching gel was because of the presence of calcium phosphate, potassium nitrate, and fluoride in the gel composition. The following null hypotheses were tested: 1) the preventive use of a nano-calcium phosphate paste will not affect the absolute risk and intensity of bleaching-induced tooth sensitivity, and 2) the preventive use of a nano-calcium phosphate paste will not affect the color change after bleaching

Methodology

Results

Discussion