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

Study Overview
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Brief Summary
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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.

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

Conditions
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Dental Caries

Intervention / Treatment
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* Drug: 5% sodium fluoride varnish
* Drug: 1.23% sodium fluoride acidic gel


Participation Criteria
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Eligibility Criteria
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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

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Negative control<br>No treatment will be applied | |
| Experimental: Varnish 4 h<br>Fluoride varnish will be applied on teeth and removed after 4 hours | Drug: 5% sodium fluoride varnish<br>* Fluoride varnish containing 22,600 ppm F, as NaF, in a neutral base<br>|
| Experimental: Varnish 24 h<br>Fluoride varnish will be applied on teeth and removed after 24 hours | Drug: 5% sodium fluoride varnish<br>* Fluoride varnish containing 22,600 ppm F, as NaF, in a neutral base<br>|
| Experimental: Fluoride Gel<br>Fluoride gell will be applied on teeth and removed after 4 minutes | Drug: 1.23% sodium fluoride acidic gel<br>* Fluoride gel containing 12,300 ppm F (as NaF) in an acidic pH (by addition of phosphoric acid)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | 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 Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in fluoride concentration in whole biofilm days after fluoride application |  | Up to 28 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Fluoride, Biofilm fluid, Calcium fluoride, Topical