Fluoride: Fad, Fact or Fiction - How fluoride safely protects teeth

Fluoride is a contentious topic these days! You may have heard about our neighbours to the South wanting to change their Federal policy to stop recommending fluoridated water, and the incredible opposition by health professionals. Or you may be aware of the City of Calgary urgently reintroducing fluoride back into their water supply after research has shown that the mean primary tooth decay (defs) increased by 3.8 - this represents a 146.15% increase! It has been used safely in many water systems, toothpastes, and dental offices for many decades. So why all the recent fuss? Let’s wade into the (possibly fluoridated 🥁💥) waters and clear up some things. Before we clear some stuff up, first we need to shore up your knowledge of fluoride and teeth so you don’t get lost in the sea of information!

What is fluoride?

It is a naturally occurring element found all over the world, in water, soil, plant, and many foods. If you dust off your periodic table from high school chemistry, it has the chemical formula “F”. It is also found in toothpastes and at your local dental offices in the form of “sodium fluoride”, or NaF. Now before we talk about what fluoride does, we need to first understand what our teeth are made of – it’s important!

What are my teeth made of?

Tooth enamel—the hardest substance in the human body—is full of a mineral called hydroxyapatite. This is a hard substance found all over the body, and for those interested, the chemical formula is Ca10(PO4)6(OH)2 – try saying that 5 times really quickly! This same mineral is also found in bone. To give you an idea of the hardness of enamel, 65-70% of the structure of your bones are full of hydroxyapatite, whereas over 90% of enamel is made up of it! This near-rock hard mineral provides us with the ability to mash up some of our favourite foods, from pizza, to burgers, and of course fruits and veggies. Now while hydroxyapatite is a tough material, it’s not invincible! Which leads us to how it breaks down – and this has a lot to do with SUGAR… (we’ll get to where fluoride comes in, promise!).

How does sugar come into play?

Sugar, one of the most delicious discoveries of mankind, also has a rather tough relationship with our teeth. Now, when we have a sugary drink or a nice sugary treat, the sugar itself doesn’t cause any damage to our teeth. However, there are many, many different kinds of bacteria that hang around our mouth – some are good, some are bad. Some of these “bad” bacteria are the ones that cause trouble to our teeth. And for those interested, some examples of the “bad” bacteria are: Streptococcus Mutans (“strep mutans”), and Lactillobacillus species. These bacteria LOVE sugar – and when they’re finished eating up and metabolizing the sugar that’s hanging around your teeth, they release ACID (for example -lactic acid). The acid hanging around your teeth is what breaks down our good friend hydroxyapatite – this is how caries, or cavities, start! So here is our road map:

1. we have a sugary treat -->

2. bacteria hanging around our teeth metabolize sugar -->

3. these bacteria produce acid -->

4. this acid breaks down our enamel -->

5. tooth decay!

With this in mind, how would our other good friend fluoride help us out?

How does fluoride help me?

Now that we know that acid-releasing bacteria hanging around our teeth are the real culprits of tooth decay, we can understand how fluoride comes into the fray. When fluoride interacts with hydroxyapatite in our enamel, it replaces the “hydroxy” in hydroxyapatite, which now becomes fluorapatite – a slightly denser mineral. And for those interested, the chemical formula is Ca10(PO4)6F2. This helps us in 2 ways:

1. fluorapatite enhances the strength of enamel, and

2. it is more acid resistant than hydroxyapatite.

This means that thanks to fluoride, our teeth are a little bit stronger, and are tougher to damage by those pesky acid producing bacteria. However, this doesn’t mean our teeth are now invincible! Fluoride is one of the many tools in our kit to help maintain our teeth. Other tools are a balanced diet, regular brushing and flossing, and of course, visiting your dentist once in a while so we can use our tools for a checkup and cleaning!

Now, one question you might have is, do we see a similar strengthening thanks to fluoride in our bones? And the answer is YES! However, the amount needed to have an effect is typically higher than the amount recommended for our teeth. We recommend consulting with your family doctor if you have concerns about bone mineral density and how best to address it.

Putting it all together

Now that we know what fluoride is, and how it works to protect our teeth, it is important to keep this information in mind when hearing all kinds of things about fluoride on TV and the internet. Next time we will cover some of these things like whether or not fluoride is bad for you, and how to detect if they are out to lunch, or on to something! We will also dig in to fluoride in water pros and cons to equip you to make the best health choices for you and your family. In the meantime, be true to your teeth or they will be false to you!