Fluoride effects: the two faces of janus.

Area of Science:

• Biochemistry
• Toxicology
• Biomaterials

Background:

• Fluoride is essential for preventing dental caries and aids bone mineralization.
• Excessive fluoride exposure can lead to toxicity, impacting human health.
• Understanding fluoride's dual role is crucial for its safe application.

Purpose of the Study:

• To review fluoride metabolism, exposure, and its effects on teeth and bone.
• To update knowledge on hypotheses regarding fluoride's mechanisms of action and toxicity.
• To propose a unifying hypothesis for fluoride's diverse biological effects.

Main Methods:

• Literature review of fluoride metabolism, exposure, and biological effects.
• Analysis of hypotheses concerning fluoride's mechanisms of action.
• Discussion of experimental models and conditions in fluoride research.

Main Results:

• Fluoride's effects are linked to G protein activation, phosphotyrosine phosphatase inhibition, and reactive oxygen species generation.
• These mechanisms can lead to increased intracellular tyrosine phosphorylation and mitogen-activated protein kinase pathway activation.
• Existing experimental data show variability, necessitating further investigation.

Conclusions:

• Fluoride exhibits a dual effect, beneficial at low doses and toxic at higher concentrations.
• Clarifying mechanisms of fluoride toxicity is essential for its therapeutic and biomaterial applications.
• Further research is required to fully elucidate fluoride's positive and negative impacts and ensure safe integration into biomaterials.