An in situ caries study on the interplay between fluoride dose and concentration in milk

Abstract

Objectives: This randomized, cross-over in situ study investigated the impact of sodium fluoride dose and concentration in milk on caries lesion rehardening, fluoridation and acid resistance.Methods: Twenty-eight subjects wore two gauze-covered enamel specimens with preformed lesions placed buccally on their mandibular partial dentures for three weeks. Participants used fluoride-free dentifrice throughout the study and consumed once daily one of the five study treatments: no fluoride in 200ml milk (0F-200), 1.5 or 3mg fluoride in either 100 (1.5F-100; 3F-100) or 200ml milk (1. 5F-200; 3F-200). After three weeks, specimens were retrieved. Knoop hardness was used to determine rehardening and resistance to a secondary acid challenge.Enamel fluoride uptake (EFU) was determined using a microbiopsy technique. were also more discerning than rehardening data. Conclusions:The present study has provided further evidence for the anti-caries benefits of fluoridated milk. Both fluoride dose and concentration appear to impact the cariostatic properties of fluoride in milk. IntroductionThe delivery of cariostatic amounts of fluoride through milk is not novel by any means as the first caries studies in children were conducted in the 1960s. Milk fluoridation has been recommended where fluoride concentration in the drinking water is suboptimal, for target groups with high caries prevalence and poor compliance for oral hygiene, in areas without or suboptimal water fluoridation and where school-or kindergarten-based programs to provide milk to children are already in place. 3,4Recent research has focused on determining if fluoride in milk follows a dose-response pattern and if an optimum fluoride concentration exists. However, results of laboratory [5][6][7] and in situ studies 8,9 into the anti-caries effects of different milk fluoride concentrations have been somewhat equivocal -benefits of fluoridated vs. non-fluoridated milk have been reported unanimously in vitro and in situ; although a clear fluoride dose-response relationship has yet to be established in situ. Likewise, there appears to be some disagreement with regards to an optimum fluoride concentration in milk as results obtained using a range of laboratory models led authors to different conclusions. 5-7Furthermore, the cariostatic properties of fluoride do not only depend on dose but also on concentration. 10While drawing parallels to conventional fluoride delivery vehicles, such as dentifrices and rinses, is not straightforward, especially considering their much higher fluoride concentrations in comparison to milk, a study on rinses demonstrated that, for a given fluoride dose, the main driving force for efficacy was fluoride concentration; i.e. rinsing with a smaller volume but higher fluoride concentration was more beneficial than rinsing with a larger volume but lower fluoride concentration.Therefore, the aims of the present in situ study were three-fold: a) the primary objective was to determine if a higher dose of fluoride in milk would provide a greater...

Protective Effect of Whole and Fat-Free Fluoridated Milk, Applied before or after Acid Challenge, against Dental Erosion

“…The F concentrations in milk tested in studies involving dental caries range from 0.25 to 10.0 ppm [Giacaman et al, 2012;Malinowski et al, 2012b;Arnold et al, 2014;Lippert et al, 2014;Ongtenco et al, 2014]. In this study, the lowest concentration used was 2.5 ppm F due to the fact that the erosive process is more aggressive than the Superscript letters indicate significant differences among the treatments.…”

Frequency of intake and amount of fluoride in milk for remineralisation of artificial caries on enamel and dentine: Ex vivo/in situ study

“…Recently, various mechanistic studies have attempted to contribute to a better understanding of the effect of fluoridated milk against caries, using in vitro and in situ models. These studies have evaluated different parameters, such as fluoride concentration in milk (Giacaman, Munoz, Ccahuana-Vasquez, Munoz-Sandoval, & Cury, 2012;Itthagarun et al, 2011;Lippert, Martinez-Mier, & Soto-Rojas, 2012;Lippert et al, 2014;Malinowski et al, 2012a;Malinowski, Duggal, Strafford, & Toumba, 2012b), temperature of milk (Lippert et al, 2012), volume of ingested milk (Lippert et al, 2014) and frequency of milk ingestion (Ongtenco et al, 2014) on the anticariogenic properties of fluoridated milk. In general, in vitro studies have reported that milk containing 2.5 ppm fluoride significantly increases enamel remineralisation and that increasing fluoride concentrations do not have an additive effect (Itthagarun et al, 2011;Malinowski et al, 2012b).…”

“…Our control group received no treatment instead of milk, since there is no programme offering non-fluoridated milk in order to prevent dental caries. Additionally, plain milk (without fluoride) has been shown to have rehardening effect similar to milk containing 1.5 mg fluoride (Lippert et al, 2014). In addition, fluoridated milk (5.0 ppm fluoride) was not significantly different from non-fluoridated milk regarding dentine demineralisation (Giacaman et al, 2012).…”

“…The results showed a positive effect of the fluoridated milk, but the group treated with sodium chloride presented a better effect (Arnold, Heidt, Kuntz, & Naumova, 2014). However, only one in situ study evaluated the influence of different fluoride concentrations in milk on enamel remineralisation, but the quantities of fluoride used added in milk (1.5 or 3.0 mg) were higher than those typically employed in milk fluoridation schemes and the authors evaluated only surface rehardening (Lippert, Martinez-Mier, & Zero, 2014).…”

Comparação de diferentes pré-tratamentos de superfície na remineralização de esmalte com flúor em tratamento de lesões com mancha branca e sua resistência após desafio ácido

“…HOOK et al, 1994;INGRAM, AGALAMANYI, HIGHAM, 2005; LIPPERT,MARTINEZ-MIER, ZERO, 2014). Acreditava-se que a principal forma de ação do flúor seria a partir da sua incorporação na estrutura dentária durante o período préeruptivo, passando a fazer parte permanentemente da estrutura formada (BIXLER;MUHLER, 1957).…”