What is the major effect of fluoridated water?

The major effect of fluoridated water is topical, as it primarily helps strengthen tooth enamel and prevent dental caries when it comes into contact with the teeth. When fluoridated water is consumed, fluoride ions are incorporated into the saliva and can interact with the tooth surfaces. This topical action enhances the remineralization of enamel, making it more resistant to acid attacks from plaque bacteria and sugars.

In addition to this topical effect, systemic benefits from fluoride occur when fluoride is ingested during tooth development, aiding in the formation of enamel. However, the immediate and most significant impact of fluoridated water for individuals with fully developed dentition is via topical exposure, as the fluoride in saliva can directly affect existing teeth.

Understanding this distinction is crucial for grasping the role of fluoride in dental health promotion. The other options, while related to fluorides' functions or modes of action in various contexts, do not represent the primary and most impactful effect of fluoridated water on dental health.