The Cavity Equation

The Cavity Equation

Our mom’s have always told us, “don’t eat all the candy, you are going to get a cavity!” So we know the relationship, more candy… more cavities. I’m going to explain to you the relationship between sugar and cavities, and how you can prevent those sugar bugs from eating holes in your teeth!

Our mouths are full of bacteria, both good and bad bacteria. How much of each, depends on how effective your daily oral hygiene is (brushing 2x a day, flossing once a day, and mouthwash 2x a day is excellent!!). Bad bacteria (streptococcus) in your mouth start to replicate and grow in numbers throughout the day. Their favorite food just happens to be sugar. When the streptococcus ‘eat’ the sugar they produce an acid. This acid lowers the pH in your mouth and is what starts to eat away at the tooth. With frequent acid attacks on your teeth, your teeth get softer and softer until a hole is formed. Once the hole has passed through the enamel, there is no going back, you’ll need a filling.

Time is also a factor. Different foods cause different lengths of acid attacks on your teeth. Sugary liquids stay on your teeth for about 20 minutes. Sugary solid foods, stay on your teeth for about 40 minutes. Therefore we have our cavity equation;

Bacteria + Sugar + Time = Demineralization of the tooth, eventually leading to a cavity.

How can we prevent cavities from forming?

1. Decrease the amount of sugar in our diets.

Remember sugar is found in so much more then just candy! Bread, juices, coffee creamers, cereals, and so much more. Be aware and always compare sugar content on the nutrition labels.

2. Decrease Bad Bacteria.

We’ve heard the routine a thousand times, brush morning and night, floss at least once a day and use mouthwash. It’s because it’s sooo important! It only takes 12 hours for bad bacteria to start out numbering the good bacteria and forming a cohesive plaque on our teeth, and less then 3 days for that plaque to harden onto our teeth. Once it’s hardened onto our teeth its called tarter and brushing and flossing won’t be able to remove it. Only your hygienist’s tools can do the job!

3. Decrease the acid attack time

A good example I always use; if you have a pack of skittles and you eat the whole pack in 10 mins, the acid attack on your teeth will be about 50 mins. But if you eat a couple skittle at a time throughout the whole day…. You are creating an acid attack on your teeth for the entire day. Therefore, one way to decrease the time is to decrease the frequency of sugar intake during the day as well.

Another way to decrease the time is to neutralize the acid after sugar intake. Eating foods that have a more basic pH works, like milk or cheese. With that being said, remember that milk has some sugars in it as well, so please do NOT put your babies to bed with a bottle of milk! Once they’ve fallen asleep, remove the bottle so there isn’t a pool of milk in their mouth the whole night. Water is by far the best option to decrease an acid attack. It neutralizes the acid in your mouth and rinses away left behind food and sugar. So if you just have to have skittles?! Please rinse your mouth with water after!

I tell patients generally to not brush right after having acidic foods or sugars. The reason is that if your mouth has a lower pH, your teeth may be a little softer due to the acid attack. Brushing could be too abrasive for the teeth at this time. It is better to rinse with water, wait a half hour and then brush with a fluoridated or calcium-phosphate toothpaste to replenish the minerals in the teeth.

Follow these steps to break the cavity equation, and I bet you’ll notice the difference at your next check up!

Here are some photos to help illustrate how cavities progress…

pits and fissures

The teeth on the left are examples of healthy molars, a little stain in the grooves is normal. The far right tooth is starting to have a chalky white appearance; these are areas where the enamel is getting weaker.


In this picture the demineralization is getting worse and you can see in the bottom left how it has now broken through the enamel causing a cavity.

extensive cavities

This picture shows deep, extensive cavities caused by sugary drinks and poor home-care.

As a dental hygienist I can’t repair cavities. But I can help you maintain a healthy mouth by seeing you at least every 6 months for a preventative cleaning and to show you and your family how to properly brush and answer any questions you may have about nutrition, oral and systemic health.

Please contact me with any questions or leave a comment below!

1 Comment

  1. Very informative blog post.Really thank you! Keep writing.


Submit a Comment

Your email address will not be published. Required fields are marked *