Condition category
Oral Health
Date applied
18/08/2014
Date assigned
04/11/2014
Last edited
04/11/2014
Prospective/Retrospective
Retrospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
Nowadays, fluoridated toothpastes are widely used and distributed throughout the world due to their preventive action against caries. Although fluoride is considered relatively safe when its concentration is equal and/or lower than 1500 ppm, it could have side effects at higher concentrations. Therefore, according to the European and American guidelines, when the fluoride concentration value is above 1500 ppm the toothpaste is only available for purchase in pharmacies with a medical prescription. The aims of this study are to compare the rate at which the fluoride is released into saliva between three toothpastes with different concentrations and evaluate their impact on salivary flow rate and possible toxic effects of fluoride exposure. The rationale is to find out whether the toothpastes with concentrations higher than 1500 ppm induce a higher fluoride intake during and after tooth brushing, compared to toothpastes with 1500 ppm of fluoride concentration.

Who can participate?
Healthy adult volunteers aged over 18 years.

What does the study involve?
Saliva will be collected from all participants at 9 and 11.30 am in the morning. They will be asked to refrain from eating and drinking (except water) for 2 hours. They will also asked not to brush their teeth at home or at work before the study appointment. During this visit they will be randomly allocated to one of two groups: intervention or control. Participants in the intervention group will be given a toothpaste high in fluoride and those in the control group will be asked to use a fluoride toothpaste available on the market. Saliva will be collected after brushing.

What are the possible benefits and risks of participating?
There are no risks associated with these interventions for the patient during or after the study.

Where is the study run from?
The Biology and Oral Biochemistry Research Group (GIBBO) laboratory at the Dentistry College of the University of Lisbon, Portugal.

When is the study starting and how long is it expected to run for?
March 2014 to December 2014.

Who is funding the study?
University of Lisbon (Portugal).

Who is the main contact?
Prof António Duarte Sola Pereira da Mata
admata3@gmail.com

Trial website

Contact information

Type

Scientific

Primary contact

Prof António Duarte Sola Pereira da Mata

ORCID ID

Contact details

Calçada dos Mestres nº3 4ºFrente
Lisbon
1070-175
Portugal

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

N/A

Study information

Scientific title

Effects of different toothpastes on fluorides kinetics release to saliva in healthy adult subjects: a three-arm parallel single-centre randomised controlled trial

Acronym

Study hypothesis

Toothpastes with different fluoride content are widely used; however, when the concentration values are above 1500 ppm, it can only be sold with medical prescription due to potential toxicity. These higher concentrations (2500 and 5000 ppm) suggest an elevated risk for systemic toxicity. The rationale is to determine whether the toothpastes with concentrations higher than 1500 ppm induce a higher fluoride intake during and after tooth brushing, comparing to toothpastes with 1500 ppm of fluoride concentration.

Hypotheses:
1. There is a significant difference in fluoride concentration present in the saliva during and after tooth brushing with different toothpastes.
2. There is a significant difference in salivary secretion induced by tooth brushing with toothpastes with different concentrations.
3. There is a significant difference in the amount of toothpaste applied to the toothbrush between the different products used in this study
4. There is a significant difference in fluoride concentration retrieved from the mouthwash and from the toothbrush after brushing with different toothpastes.

Ethics approval

Dentistry College of the University of Lisbon; 12/02/2014

Study design

Three-arm parallel single-centre blind randomised controlled trial

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Hospitals

Trial type

Screening

Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet

Condition

Healthy adult volunteers

Intervention

Salivary secretion capacity will be assessed in all participants at baseline.

The participants will randomly be allocated to the control and intervention arms in equal numbers (22 in each arm):
1. Intervention arm: fluoride highly concentrated dentifrices such as Fluor aid 250® (Dentaid S.L., Spain) and Colgate Duraphat® (Colgate-Palmolive Unipessoal, LDA, Portugal)
2. Control arm: traditional dentifrice, sold freely, Colgate Total® (Colgate-Palmolive Unipessoal, Lda; Portugal),

Salivary secretion rate and fluoride concentration will be recorded at defined time intervals (before toothbrushing at 0 and 10 minutes; after toothbrushing at 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 110 and 120 minutes) to determine if the amount of fluoride would be able to induce toxic effects in the human body.

Intervention type

Drug

Phase

Not Applicable

Drug names

Fluor aid 250, Colgate Duraphat, Colgate Total

Primary outcome measures

Amount of fluoride present in saliva during and after toothpaste use, expressed in milligrams, as the mean ± 95% confidence interval.

Fluoride present in the toothbrush, mouthwash and in saliva after toothpaste use, expressed in parts per million will be determined using metric techniques and a fluoride selective electrode. This value will be converted into milligrams, according to each dentifrice and its fluoride concentration. Percentage values will be determined, considering the toothpaste placed on the toothbrush (expressed in grams, and calculated from the difference of weight of the toothbrush before and after toothpaste placement) as the total amount of fluoride, meaning 100% of fluoride of exposure. All the fluoride accumulated in saliva will be determined and, based on this value, calculation will be performed for each dentifrice to determine how many times a patient would have to brush his teeth per day to cause any deleterious effect, according to the reference values for acute and chronic fluoride toxicity in the literature.

Secondary outcome measures

1. Concentration of fluoride present in saliva before, during and after toothpaste use, expressed in parts per million, as the mean ± 95% confidence interval
2. Amount of paste placed in the toothbrush, expressed in grams, as the mean ± 95% confidence interval
3. Fluoride wasted in the toothbrush and in the mouthwash, expressed in grams, as the mean ± 95% confidence interval
4. Fluoride wasted in the toothbrush and in the mouthwash, expressed in ppm, as the mean ± 95% confidence interval
5. Fluoride present in the toothbrush, mouthwash and in saliva after toothpaste use, expressed in percentage, as the mean ± 95% confidence interval
6. Salivary flow after brushing with the dentifrices, expressed in milliliters per minute, as the mean ± 95% confidence interval

Overall trial start date

19/03/2014

Overall trial end date

30/12/2014

Reason abandoned

Eligibility

Participant inclusion criteria

1. Above 18 years
2. An unstimulated whole saliva flow higher than 0.1 mL/min
3. Healthy volunteers, without any systemic pathologies

Participant type

Healthy volunteer

Age group

Adult

Gender

Both

Target number of participants

66

Participant exclusion criteria

1. Pregnant
2. Medication that induce xerostomia
3. Does not meet inclusion criteria

Recruitment start date

19/03/2014

Recruitment end date

30/12/2014

Locations

Countries of recruitment

Portugal

Trial participating centre

Calçada dos Mestres nº3 4ºFrente
Lisbon
1070-175
Portugal

Sponsor information

Organisation

University of Lisbon (Portugal)

Sponsor details

School of Dental Medicine
Biology and Oral Biochemistry Research Group (GIBBO) laboratory
Cidade Universitária
Lisbon
1649-003
Portugal

Sponsor type

University/education

Website

http://www.fmd.ul.pt

Funders

Funder type

University/education

Funder name

University of Lisbon (Portugal) - School of Dental Medicine; GIBBO research unit

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes