Fluoride has been shown to do two very important things: it slows bacteria growth and strengthens teeth surfaces.
Slowing Bacteria Growth
Fluoride inhibits the way bacteria utilizes sugar and grow, this eventually stops them from multiplying and releasing acids. While fluoride is brushed onto your teeth, it also bonds to the substructure of your teeth surfaces, making them much tougher than before. Now your teeth are a lot more resistant to the acids and if your teeth start to dissolve it would release the fluoride bonded to the surface and inhibits bacteria growth again.
Topical fluoride is not the same as systemic ingested fluoride. We strongly recommend topical fluoride such as fluoride found in toothpaste, mouthwash, and varnish because they're generally not ingested. We understand a very small amount can be swallowed, but the amount is minuscule and does not post a threat to our health.