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How does fluoride in drinking water help reduce tooth decay?

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Dentistry — dentistry The practice of dentistry involves preventing, diagnosing, and treating oral disease, as well as correcting deformities of the jaws, teeth, and oral cavity.

Fluoride in drinking water helps reduce tooth decay primarily by strengthening tooth enamel and inhibiting the bacteria that cause cavities.12

At the surface of the teeth, fluoride facilitates the attachment of calcium and phosphate ions, which promotes the formation of fluorapatite crystals. This process helps to remineralize enamel, making teeth more resistant to decay.23

Additionally, fluoride present in saliva works to protect teeth by:
* Blocking bacterial activity: It interferes with the enzymes of bacteria that contribute to tooth decay, thereby decreasing the production of harmful acids.2
* Reducing adhesion: It inhibits the ability of these bacteria to grow and adhere to the tooth surface.2

By maintaining an optimal concentration—typically 0.7 parts per million—water fluoridation is recognized as an effective public health measure that significantly reduces the prevalence of dental caries in both children and adults.12