Conditions: Tooth Bleaching Tooth Sensitivity
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 108
Healthy volunteers: yes

Brief summary:
The aim of this clinical study is to evaluate the efficacy and dental sensitivity associated with Combined Bleaching Technique (in-office + at-home) varying in-office bleaching application under two different time protocols, and dentifrice containing arginine 8% and carbonate calcium use. One hundred eight participants who meet the study inclusion criteria will be selected. The desensitizing agent used will be a dentifrice containing 8% arginine and calcium carbonate. In each evaluation will be determined: tooth sensitivity and color. The data collected will be submitted to the factorial statistical analysis for evaluation of color and chi-square test for tooth sensitivity (α = 5%).

Detailed description:
This study will be conducted under the CONSORT recommendations. After approval by the Ethics Committee for Research duly registered, the trial will be conducted in the clinic of dental school at the Federal University of Goias located in Goiania. One hundred eight participants 108 volunteers will be selected on the criteria that qualify inclusion and exclusion from the study will be reported all volunteers were examined not qualify under the criteria for inclusion as part of the initial according to CONSORT recommendations .

After signing the signed an informed consent form all volunteer participants will receive a dental prophylaxis with pumice and water in a rubber cups for the removal of extrinsic stains two weeks before the beginning of tooth whitening.

Arms:
arm 1: In-office: 35% hydrogen peroxide of 20 minutes each. At-home: 10% carbamide peroxide arm 2: Combined Bleaching(2x20) with arginine In-office: 35% hydrogen peroxide of 20 minutes each. At-home: 10% carbamide peroxide Desensitizing agent: dentifrice containing 8% arginine and calcium carbonate. arm 3: In-office: 35% hydrogen peroxide of 20 minutes each. At-home: 10% carbamide peroxide arm 4: Combined Bleaching(1x20) with arginine In-office: 35% hydrogen peroxide of 20 minutes each. At-home: 10% carbamide peroxide Desensitizing agent: dentifrice containing 8% arginine and calcium carbonate.

Interventions: intervention 1: Combined Bleaching(2x20) intervention 2: Combined Bleaching(2x20) with arginine intervention 3: Combined Bleaching (1x20) intervention 4: Combined Bleaching(1x20) with arginine intervention 5: 8% arginine and calcium carbonate
Intervention descriptions: intervention 1: one clinical session with two applications of 35% hydrogen peroxide of 20 minutes each. 10% carbamide peroxide for two hours daily over the course of two weeks. intervention 2: one clinical session with two applications of 35% hydrogen peroxide of 20 minutes each. 10% carbamide peroxide for two hours daily over the course of two weeks. intervention 3: one clinical session with one application of 35% hydrogen peroxide of 20 minutes each. 10% carbamide peroxide for two hours daily over the course of two weeks. intervention 4: one clinical session with one application of 35% hydrogen peroxide of 20 minutes each. 10% carbamide peroxide for two hours daily over the course of two weeks. intervention 5: using during all the treatment.

Protocol document:
Prot_SAP_000.pdf: 
Combined Bleaching Technique: Efficacy and Tooth Sensitivity - A Randomized, 
Double Blind Clinical Trial 
 
ClinicalTrials.gov ID: NCT03089216 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
May 1, 2018 


Objective 
 
This study evaluated the efficacy, color stabilization, and tooth sensitivity 
(TS) during and after the use of a combined bleaching technique, varying the 
application time of 35% hydrogen peroxide (HP) and the use of a desensitizing 
dentifrice containing arginine (ARG).  
 
Study design 
 
This is a randomized controlled clinical trial, parallel and double blinded, with 
a similar allocation rate between groups, registered at clinicaltrials.gov under the 
identification number NCT03089216. The study has being conducting at the School 
of Dentistry of the Federal University of Goias (UFG), following CONSORT 
statement, after the approval of the Ethics Committee of the Federal University of 
Goias, Brazil (CAAE: 52047115.2.0000.5083). 
One hundred and eight participants were randomly assigned to 4 groups (n = 
27): OFF40 (without ARG): two 20-minute HP applications (2x20); D-OFF40 (with 
ARG): two 20-minute applications (2x20); OFF20 (without ARG): one 20-minute HP 
application (1x20); and D-OFF20 (with ARG): one 20-minute HP application (1x20). 
In all groups, at-home bleaching was performed with 10% carbamide peroxide (CP) 
for two hours daily for 16 days. Color evaluations were performed before bleaching 
and at 5, 8, 12, and 16 days from the beginning of the procedure, and 7 and 30 days 
after the end of the treatment, with VITA Classical and VITA Bleachedguide 3D-
MASTER shade guides (SGU) and a digital spectrophotometer, VITA Easyshade 
(VITA Zahnfabrik). The TS evaluation was performed with a visual analogue scale 
(0-10) and numerical scale (0-4) in different periods.  
 
Statistical Analysis Plan 
 
Statistical analyses will be performed using SPSS 20.0 (SPSS Inc., Chicago, 
IL, USA) with  = 0.05. The means of the SGU at baseline and after different 
assessments will be calculated for each group. In order to evaluate whether the 
bleaching therapies were effective or not, the data from the SGUs will be analyzed 
using the Kruskal-Wallis and Mann-Whitney tests for between-group comparisons, 


and the Friedman and Wilcoxon tests with Bonferroni correction ( = 0.002) for 
within-group comparisons. The ΔE values will be submitted to two-way analysis of 
variance (ANOVA). 
The Tooth Sensitivity intensity will be analyzed using Kruskal- among-group 
comparisons within each evaluation time (baseline, immediately after the in-office 
bleaching, daily during the at-home bleaching, and up to 48 hours after the treatment). 
The comparisons among the assessment times within each group will be performed 
using the Friedman and Wilcoxon tests with Bonferroni correction ( = 0.008).