Let's start with what fluoride is. It is the fluorine ion that's added to toothpaste, mouthwash, and sometimes even to your drinking water to help prevent cavities from happening. But does it work? While increasing the "concentration of systemic fluoride (that is through fluoridating drinking water) has not been proven to reduce the incidence of tooth decay, direct contact between fluoride and teeth helps to strengthen and remineralize damaged tooth enamel." So in a way, yes, it does help. It's just not direct.
Tooth enamel is made up of calcium and a phosphate compound that is a modified form of hydroxyapatite. That, in turn, is susceptible to attack by acids found in the human mouth. Bacteria that thrive on the sugars found in the mouth multiply on dental surfaces and produce those acids.
Brushing your teeth helps to dislodge the bacteria and rinses them away. But brushing alone doesn't do much to address the ongoing damage done to enamel by the exposure to these acids. The saliva in your mouth does, fortunately, help to neutralize these acids. And, did you know, that compounds found in your saliva work to remineralize your tooth enamel? It's true. "So, as long as the rate of demineralization and the rate of remineralization remain in balance, teeth remain strong and healthy." But when more minerals are lost from teeth than get replaced, dental cavities form. Fluoride helps by interacting with hydroxyapatite to form a stronger compound that is less susceptible to acid attack. Although fluoride remineralizes tooth enamel it won't help to repair a cavity once it's there.
Despite the fact that you probably spit out your toothpaste and rinse your mouth with water and mouthwash, enough fluoride remains on the teeth and in your saliva to help protect your teeth for a little while.
I probably have more teeth than most frogs so I found this information helpful. I hope that you as a human with lots of teeth, found this little tidbit about fluoride useful, as well. Tomorrow I have a special blog celebrating some unlikely froggy friends. I hope you'll stop back by and say hello (and maybe read the blog, too)! Until then, I wish you all a glorious thursday and may your life be filled with