Long-term Release of Fluoride Formed on Enamel by Fluoride Gel or Varnish to Biofilm Fluid

Retention of Fluoride Formed on Enamel by Fluoride Gel or Varnish Application and Its Release to Dental Biofilm Fluid - in Vivo Study

Status

Completed

Phases

Early Phase 1

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT02486458

Enrollment

Registered

2015-07-01

Start date

2015-04-30

Completion date

2016-12-31

Last updated

2017-05-09

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Dental Caries

Keywords

Fluoride, Biofilm fluid, Calcium fluoride, Topical

Brief summary

The anticaries effect of professional fluoride application has been associated with the formation of calcium fluoride-like products (CaF2) on dental surface, which may function as a slow release fluoride reservoir. Among professional fluoride products, fluoride gel and varnish are the most important, and have different soluble fluoride concentrations, pHs and vehicles. Although the concentration of fluoride formed on enamel after the use of both is similar, the retention of these reaction products is unknown. Also, it is unknown the capacity of these reservoirs to enhance dental biofilm fluid with fluoride. Moreover, the effect of the varnish application time on these parameters is unknown. Therefore, the aim of this study is to compare the capacity of fluoride gel and varnish to form fluoride reservoirs on enamel and increase dental biofilm fluid fluoride concentration with time. Rapid biofilm-forming individuals will be selected to participate and divided into 4 experimental groups: 1. Negative control: no treatment; 2. Varnish 4 hours: fluoride varnish will be applied and kept on teeth for 4 hours; 3. Varnish 24 h: fluoride varnish will be applied on teeth and kept for 24 h; and 4. Gel: Fluoride gel will be applied on teeth. Microbiopsies of enamel will be obtained by a microbiospy technique to assess fluoride concentration before, 7 and 28 days after the treatments. Dental biofilm will be collected before and 3, 7, 14 and 28 days after treatments. Fluoride concentration on enamel and in the biofilm fluid will be determined by an ion-specific electrode. Data will be analyzed statistically comparing the groups and collection times.

Interventions

DRUG5% sodium fluoride varnish

Fluoride varnish containing 22,600 ppm F, as NaF, in a neutral base

DRUG1.23% sodium fluoride acidic gel

Fluoride gel containing 12,300 ppm F (as NaF) in an acidic pH (by addition of phosphoric acid)

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

PREVENTION

Masking

DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender

ALL

Age

18 Years to 30 Years

Healthy volunteers

Yes

Inclusion criteria

* Good general health * Good oral health * At least 5 teeth in each hemiarch * All 4 superior incisors in the mouth * Rapid biofilm forming

Exclusion criteria

* Pregnancy * Intake of medication that reduces salivary flow * Chronic diseases * Smokers * Orthodontic appliances * Dental prosthesis * Allergy to fluoride varnish components

Design outcomes

Primary

Measure	Time frame
Change in fluoride concentration in enamel days after fluoride application	Up to 28 days
Change in fluoride concentration in dental biofilm fluid days after fluoride application	Up to 28 days

Secondary

Measure	Time frame
Change in fluoride concentration in whole biofilm days after fluoride application	Up to 28 days

Countries

Brazil

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026