Clinical trial NCT02741427: Efficacy of a Whitening Dentifrice on Tooth Discoloration
Official title: Safety, Acceptability and Efficacy of a Silica Dentifrice Containing Blue Pigment on Tooth Whitening: a Randomized Clinical Trial
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Tooth Discoloration
Keywords: Tooth discoloration
Toothpaste
Tooth bleaching
Clinical trial
Lead sponsor: Federal University of Paraíba
Sponsor class: OTHER
Collaborators: name: Unilever R&D
First posted: 2016-04-18
Enrollment: 75
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The purpose of this study was to compare the whitening effect of a toothpaste containing blue pigment with a conventional toothpaste and with at-home tooth bleaching; evaluate the subject's perception about tooth color improvement and; and evaluate the safety and acceptability of these products.

Detailed description: The study was approved by local Ethical Committee under protocol number CAAE: 035541412.7.0000.5188, and each volunteer signed an informed consent form prior to enrollment in the study.

The sample size calculation was carried out based on a previous study. To detect the bleaching effect with a power of 80% and a one-tailed alpha error of 5%, a sample size of 20 subjects in each treatment group was necessary to detect a 20% difference between groups in shade change. A 20% addiction in subjects' number, taking into consideration potential loss or refusal, gave a total sample size of 75 subjects (25 in each group). The individuals were invited to participate in this clinical trial through advertisement exposed at the Federal University of Paraíba, Brazil.

Basing on eligibility criteria, 75 volunteers were selected to the trial and randomized to one of the three groups of treatment: G1- brushing teeth with a conventional toothpaste; G2- brushing teeth with a silica whitening dentifrice containing blue pigment; and G3 - at-home tooth bleaching with 10% carbamide peroxide. The treatments will be detailed in another section. It was used a simple randomization to allocate the subjects, and a randomization table was prepared in the Excel Program by a member, not directly involved with the clinical part of the study.

To mask the products used in the treatment groups, each toothpaste type was enveloped with an adhesive tape of a different color and the seal of the bleaching gel syringe was removed. The same examiner responsible for subject allocation did this procedure. Thus, testing with the toothpastes was double-blinded, where both evaluator and subject did not know which toothpaste was being used.

The outcomes evaluated were: tooth shade, subjects' perception about tooth color appearance, and safety and acceptability of products tested, which were measured at baseline, 2-weeks, 3-weeks and 4-weeks of the beginning of treatments.

For statistical analysis, data were checked for normal distribution using the Kolmogorov Smirnov test, and then it was applied the appropriated parametric or non-parametric tests. Differences were considered statistically significant when p \< 0.05.

Eligibility criteria: Inclusion Criteria:

* To have six maxillary anterior teeth with a mean shade of C1 or darker (Vitapan Classical, Vita Zahnfabrik, Bad Sackingen, Germany),

Exclusion Criteria:

* With active caries or periodontal disease,
* Presenting non-vital anterior teeth,
* Previous hypersensitivity,
* Under orthodontic treatment,
* With structural defect in the enamel,
* Who had used tooth whiteners within the previous 3 years,
* Smokers,
* Pregnant or lactating

Primary outcomes:
measure: Tooth shade changes from baseline until 4 weeks of the beginning of intervention
timeFrame: Baseline, Immediately after first product application, 2 weeks and 4 weeks of the beginning of interventions
Secondary outcomes:
measure: Subjects' perception about improvement on tooth color
timeFrame: 2 weeks of the beginning of interventions
measure: Tooth sensitivity and gingival irritation evaluation
timeFrame: Daily during three weeks
measure: Acceptability of interventions
timeFrame: 2 weeks of the beginning of interventions
Other outcomes:
Locations:
Study officials:
affiliation: Federal University of Paraiba
name: Jossaria P Sousa, Master
role: PRINCIPAL_INVESTIGATOR
References:
citation: Meireles SS, Santos IS, Bona AD, Demarco FF. A double-blind randomized clinical trial of two carbamide peroxide tooth bleaching agents: 2-year follow-up. J Dent. 2010 Dec;38(12):956-63. doi: 10.1016/j.jdent.2010.08.003. Epub 2010 Aug 13.
citation: Walsh TF, Rawlinson A, Wildgoose D, Marlow I, Haywood J, Ward JM. Clinical evaluation of the stain removing ability of a whitening dentifrice and stain controlling system. J Dent. 2005 May;33(5):413-8. doi: 10.1016/j.jdent.2004.10.021. Epub 2004 Dec 20.