Considerations on Optimal Fluoride Intake Using Dental Fluorosis and Dental Caries Outcomes – A Longitudinal Study

Abstract

Objectives The “optimal” intake of fluoride has been widely accepted for decades as between 0.05 and 0.07 mg fluoride per kilogram of body weight but is based on limited scientific evidence. The purpose of this paper is to present longitudinal fluoride intake data for children free of dental fluorosis in the early-erupting permanent dentition and free of dental caries in both the primary and early-erupting permanent teeth as an estimate of optimal fluoride intake. Methods Data on fluoride ingestion were obtained from parents of 602 Iowa Fluoride Study children through periodic questionnaires at the ages of 6 weeks, 3, 6, 9, 12, 16, 20, 24, 28, 32 and 36 months, and then at 6-month intervals thereafter. Estimates of total fluoride intake at each time point were made by summing amounts from water, dentifrice, and supplements as well as other foods and beverages made with or containing water. Caries data were obtained from examinations of children at ages 5 and 9 years, while fluorosis data were obtained from examinations only at age 9. Results The estimated mean daily fluoride intake for those children with no caries history and no fluorosis at age 9 was at or below 0.05 mgF/kg bw for nearly all time points through the first 48 months of life, and this level declined thereafter. Children with caries had generally slightly less intakes, while those with fluorosis generally had slightly higher intakes. Conclusions Given the overlap among caries/fluorosis groups in mean fluoride intake and extreme variability in individual fluoride intakes firmly recommending an “optimal” fluoride intake is problematic.

<b>Knowledge of pediatricians and the importance of interdisciplinarity in attention to oral health in early childhood

“…The mechanism of action of fluoride in fluorosis, contrary to what occurs in relation to tooth decay, is dose dependent, i.e. the development of fluorosis depends on the quantity ingested (Warren et al, 2009).…”

Outcome of a public consultation on the Draft Scientific Opinion of the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) on Dietary Reference Values for fluoride

“…It is estimated that fluorosis will occur where ingested fluoride is above 0.03-0.04mg/kg which, if the only source of fluoride is in drinking water, would mean that an average 1 year old (10kgs) will exceed this if drinking more than 0.3/0.4 litres per day and an average 6 year old (22kgs) 0.66-0.88 litres per day. However as studies show children under 5 years old ingest some 30% of their toothpaste and fluoride is also found in prepared foodstuffs from pesticide residues and preparation processes if in areas with water fluoridation (Warren et al 2009).…”

“…Warren et al (2009) have highlighted the complexity of quantifying fluoride intake in areas where there is widespread water fluoridation and increased availability of fluoride-containing products. They argue that " .…”

“…In their analysis of fluoride ingestion and dental caries and fluorosis experience Warren et al (2009) highlight the complexity of quantifying fluoride intake in areas where there is widespread water fluoridation and increased availability of fluoride countaining products arguing that assessing children"s fluoride intake is virtually impossible and thus rendering a concept of taregt intake useless. The term optimal fluoride intake be dropped from common usage (Warren et al 2009: 115, Burk andEklund 2005).…”

“…Dean had admitted under oath that he had carefully selected the datapoints of his published graph showing minimum caries experience with 1-2 ppm F ¯ naturally in US water supplies. Warren (2009) concluded that, based on individual F ¯ intakes up to 4 years, deriving any "optimal" intake rate was "problematic" -there being such wide intake ranges from zero upwards in individual children and There is sound experimental and clinical justification for supplementing oral F ¯ levels regularly in order to reinforce outermost enamel resistance to caries but the great majority of dentists are well aware that the inevitable accompanying F ¯ internalisation should be minimised as effectively as possible. This supports the use of modern fluoride varnishes to control childhood caries as effectively and safely as possible.…”