From the Guidelines
Fluoride prevents tooth decay by strengthening tooth enamel and making it more resistant to acid attacks, and its use is recommended for all individuals to minimize the risk of dental caries. When fluoride is present in the mouth, it becomes incorporated into the structure of developing teeth, creating a stronger mineral called fluorapatite that is less soluble in acid than natural tooth enamel 1. Additionally, fluoride promotes remineralization, helping to repair early stages of tooth decay by attracting calcium and phosphate ions to damaged areas. It also inhibits bacterial activity in plaque by interfering with enzymes that bacteria use to metabolize sugars, reducing their ability to produce the acids that cause decay.
The mechanisms by which fluoride exerts its effects include:
- Inhibiting demineralization of tooth enamel and facilitating tooth remineralization 1
- Releasing fluoride from dental plaque in response to lowered pH at the tooth-plaque interface, which is then taken up by demineralized enamel to establish an improved enamel crystal structure 1
- Being more readily taken up by demineralized enamel than by sound enamel, allowing for targeted repair of damaged areas 1
For optimal protection, dentists recommend:
- Using fluoride toothpaste twice daily (containing 1000-1500 ppm fluoride for adults) 1
- Drinking fluoridated water where available 1
- Receiving professional fluoride treatments during dental checkups 1
- Children should use age-appropriate fluoride toothpaste amounts - a rice-sized smear for children under 3 and a pea-sized amount for children 3-6 years old to balance decay prevention with minimizing fluorosis risk 1
Overall, the use of fluoride is a safe and effective way to prevent and control dental caries, and its benefits have been consistently demonstrated in numerous studies 1.
From the Research
How Fluoride Prevents Tooth Decay
- Fluoride is a key component in the prevention and control of tooth decay, with multiple fluoride modalities available, each with its own effectiveness and safety profile depending on dose and concentration 2.
- The use of fluoride toothpaste is the primary intervention for the prevention of caries, with higher concentrations of fluoride associated with increased caries control 3, 4.
- Fluoride can affect bacterial metabolism, acting as an enzyme inhibitor, and can also enhance membrane permeabilities to protons, compromising the functioning of F-ATPases and inducing cytoplasmic acidification, thereby reducing the acid tolerance of bacteria 5.
Mechanisms of Fluoride in Preventing Tooth Decay
- Fluoride has a weak-acid character, which allows it to enhance membrane permeabilities to protons and compromise the functioning of F-ATPases, leading to cytoplasmic acidification and acid inhibition of glycolytic enzymes 5.
- The antibacterial actions of fluoride are complex, involving effects on bacteria and mineral phases, with the weak-acid effects being the most pertinent to reducing the cariogenicity of dental plaque 5.
- Fluoride can also form metal-fluoride complexes, which are responsible for fluoride inhibition of proton-translocating F-ATPases, and can act by mimicking phosphate to form complexes with ADP at reaction centers of the enzymes 5.
Effectiveness of Fluoride in Preventing Tooth Decay
- The caries-preventive effect of fluoride toothpaste increases significantly with higher fluoride concentrations, with concentrations of 1000 ppm and above showing a statistically significant effect when compared to placebo 3, 4.
- The relative caries preventive effects of fluoride toothpastes of different concentrations increase with higher fluoride concentration, with a dose-response relationship observed in some studies 3, 4.
- The use of fluoride toothpaste in conjunction with other fluoride sources, such as fluoridated water, can have additive preventive effects, providing substantial lifelong caries prevention and reducing health inequalities 6.