Fluoride Bioavailability After Ingestion of Water or Foods Prepared With Fluoridated Water

Study Overview
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Brief Summary
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The importance of fluoridated water to control caries is well recognized. Although the mode of action of fluoridated water is known (related to a slight increase in fluoride concentration in saliva/dental biofilm in individuals living in fluoridated areas), the kinetics of fluoride concentration in saliva after ingestion of food prepared with fluoridated water, either from fluoride remaining in the oral cavity after mastication, or from fluoride returning from salivary secretion is not known in details. Therefore, the aim of this study is to assess fluoride bioavailability after ingestion of food prepared with fluoridated water. The study will be in vivo, crossover and double blind, in which 12 adult volunteers will participate. In 4 experimental phases, volunteers will ingest: a. a typical Brazilian meal cooked with non-fluoridated water (<0.1 ppm F); b. a typical Brazilian meal cooked with fluoridated water (1 ppm F); c. non fluoridated water (<0.1 ppm F) and d. fluoridated water (1 ppm F). Immediately before and 5, 10, 15, 30, 45, 60, 120, 180 minutes after the ingestion, a blood sample will be collected by digital puncture, and a sample of unstimulated saliva will be collected. Fluoride concentration in the samples will be determined by an ion specific electrode adapted for microanalysis. Results will be analyzed by ANOVA, with significance limit of 5%.

Official Title
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Fluoride Bioavailability in Plasma and Saliva After Ingestion of Water or Foods Prepared With Fluoridated Water

Conditions
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Dental Caries, Dental Fluorosis

Intervention / Treatment
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* Other: Meal prepared with non fluoridated water
* Other: Meal prepared with fluoridated water
* Other: Non fluoridated water
* Other: Fluoridated water
* Other: Meal prepared to provide a fluoride dose of 60 ug F/kg
* Other: Meal prepared to provide a fluoride dose of 120 ug F/kg


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Good general health Good oral health Normal salivary flow rate Exclusion criteria: Gastric disorders Renal disorders Systemic diseases Use of drugs that alter salivary flow rate/renal excretion

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 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: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Meal prepared with non fluoridated water (<0.1 ppm F)<br> | Other: Meal prepared with non fluoridated water<br>* Ingestion of a typical brazilian meal (rice, beans, meat, french beans, carrots, gelatin and juice) prepared with purified water containing a fluoride dose of 0.8 ug of fluoride/kg body weight (resulting of the natural fluoride concentration in foods).<br>|
| Experimental: Meal prepared with fluoridated water (1 ppm F)<br> | Other: Meal prepared with fluoridated water<br>* Ingestion of a typical brazilian meal (rice, beans, meat, french beans, carrots, gelatin and juice) prepared with fluoridated water (1 ug of fluoride/mL), to provide a total intake of approximately 12 ug of fluoride/kg body weight.<br>|
| Experimental: Non fluoridated water (<0.1 ppm F)<br> | Other: Non fluoridated water<br>* Ingestion of purified water with addition of fluoride to provide a total intake of approximately 0.8 ug of fluoride/kg body weight, which represented the same fluoride ingestion dose of the experimental phase with meal prepared with non fluoridated water.<br>|
| Experimental: Fluoridated water (1 ppm F)<br> | Other: Fluoridated water<br>* Ingestion of fluoridated water (1 ug F/mL), to provide a total intake of approximately 12 ug of fluoride/kg body weight.<br>|
| Experimental: Pilot study: Meal providing a fluoride dose of 60 ug F/kg<br> | Other: Meal prepared to provide a fluoride dose of 60 ug F/kg<br>* Ingestion of a typical Brazilian meal (rice, beans, meat, french beans, carrots, gelatin and juice) prepared with non-fluoridated water, with sodium fluoride solution added to the juice to provide a total intake of approximately 60 ug of fluoride/kg body weight.<br>|
| Experimental: Pilot study: Meal providing a fluoride dose of 120 ug F/kg<br> | Other: Meal prepared to provide a fluoride dose of 120 ug F/kg<br>* Ingestion of a typical Brazilian meal (rice, beans, meat, french beans, carrots, gelatin and juice) prepared with non-fluoridated water, with sodium fluoride solution added to the juice to provide a total intake of approximately 60 ug of fluoride/kg body weight.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Area under the curve of plasma fluoride concentration versus time after water or food ingestion | A microsample of blood will be collected by digital puncture before and 5, 10, 15, 30, 45, 60, 120 and 180 min after treatments, to calculate the area under the curve of fluoride concentration in the plasma | 180 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Area under the curve of salivary fluoride concentration versus time after water or food ingestion | A sample of unstimulated saliva will be collected by digital puncture before and 5, 10, 15, 30, 45, 60, 120 and 180 min after treatments, to calculate the area under the curve of fluoride concentration in saliva | 180 minutes | 
| Maximum fluoride concentration in saliva after water or food ingestion |  | 180 minutes | 
| Maximum fluoride concentration in plasma after water or food ingestion |  | 180 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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pharmacokinetics, saliva, plasma, fluoride, dental fluorosis, dental caries