Is There A Limit To How Many Times You Should Brush Your Teeth In A Day?

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Brushing your teeth twice a day is recommended, but depending on your diet, you may benefit from brushing more frequently. How you brush is also equally important.

Growing up, we were repeatedly told by our elders and parents to “brush your teeth” before going to bed or after waking up in the morning. You probably recall the groggy mood you were in as you slowly walked your half-asleep body to the bathroom, picked up the toothbrush, lazily added some toothpaste, and brushed your teeth in a decidedly unmotivated manner.

Eventually, such a routine becomes a habit, so you can thank your own self-motivation and your parents’ nagging for your decent oral hygiene.

We know what happens if we don’t brush enough, but what happens if we brush too much?

For all my Brooklyn Nine-Nine fans, remember when Amy Santiago over-brushed her teeth aggressively, which led to her getting 7 cavities? This was because she wore away the protective enamel of her teeth by brushing too much!

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What Is Enamel?

Enamel is a protective layer that covers each individual tooth, sealing it away from teeth-harming bacteria that flourish in the mouth. It is also a shield against the harmful effects of plaque that builds up on our teeth, as well as the acids that are present in the food we eat.

Underneath the enamel lies the dentine, which is the hard and dense bony tissue that composes the bulk of the tooth.

Enamel is the hardest tissue in the body. It is incredibly mineralized, which is why our teeth can withstand decades of chewing all types of food, especially the junk foods that we like so much, which are bad for our teeth. Candy lovers will certainly know what I’m talking about.

Enamel is composed of 95% hard mineral, called carbonated hydroxyapatite (HAP) and 4% water, while the remaining 1% is made of soft organic matter. Enamel is very important, as it provides protection to our teeth.

Human tooth structure vector diagram(Siberian Art)s
Structure of our shiny and white teeth (Photo Credit : Siberian Art/Shutterstock)

Tooth Wear

Incorrect, aggressive, or excessive brushing has been linked to the wearing down of tooth enamel. This “wearing out” is called tooth-wear. Simply put, tooth-wear is the loss of tooth tissue.

Sadly, our body does not make more enamel, as there are no cells that produce it.

Studies have shown that the canines and pre-molars tend to be the teeth that receive the most attention while brushing, and are thus more prone to tooth-wear.

Also Read: How Do Cavities Form In Teeth?

RDA Value Of Toothpastes

Toothpastes contain abrasives meant to remove plaque from the surfaces of our teeth. While scrubbing off the plaque, they do also cause a small amount of enamel erosion. Each type of toothpaste has an RDA (Relative dentin abrasivity) value that is a measure of its abrasive effect.

It is recommended that you use toothbrushes and toothpastes with an RDA value of 250 or less. This ensures limited wear to the dentine and enamel.

One interesting study reported a loss of dentine in people who brushed with toothpaste four times a day for 60 seconds over 15 days, but there was little effect on enamel.

Also Read: How Does Toothpaste Work?

Electric Toothbrushes Or Manual Toothbrushes?

Now, toothbrushes alone, whether electric or manual, barely have any effect on enamel or dentine without toothpaste, but no one really brushes without toothpaste. Thus, we have to compare electric and manual brushing with toothpaste.

Electric and manual toothbrushes(Ugis Riba)s
Electric and manual toothbrushes (Photo Credit : Ugis Riba/Shutterstock)

Logically, one would assume that electric toothbrushes, with the force of motorized movements, would cause more wear and tear to the enamel and dentine. That is, however, not the case.

Studies show that electric toothbrushes are more efficient than manual toothbrushes in removing plaque and germs from the surface of our teeth because we tend to use less force when scrubbing an electric toothbrush against our teeth, as compared to a manual one.

So, while it is proven that excessive brushing increases the wearing down of dentine and enamel, it is still not enough to cause harm to our teeth. In fact, brushing normally with toothpaste will still require years and years of normal use to remove around l mm of dentine.

If you’re still unsure about brushing excessively and are now worried about doing more harm than good, you could switch to using soft or medium toothbrushes instead of hard ones. They are much easier on the teeth and allow room for a little aggressiveness while brushing without harming your teeth.

different type of brush
I visited the birthplace of the person who invented the toothbrush; there was no plaque. (Photo Credit : Pexels)


Overall, brushing is still very necessary, especially if you want people to stand anywhere close to you when you’re talking. Follow the recommended standard of brushing twice a day, and if you have a lot of soft drinks, or sticky candy, then it would definitely be wise to brush more often. Leaving these unhealthy substances on your teeth will cause more harm than what might occur from excessive brushing.

aggressive healthy dental care and hygiene routine in the bathroom for beautiful young woman(STUDIO GRAND WEB)s
Remember not to be too aggressive in your brushing (Photo Credit : STUDIO GRAND WEB/Shutterstock)

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References (click to expand)
  1. Beniash, E., Stifler, C. A., Sun, C.-Y., Jung, G. S., Qin, Z., Buehler, M. J., & Gilbert, P. U. P. A. (2019, September 26). The hidden structure of human enamel. Nature Communications. Springer Science and Business Media LLC.
  2. Addy, M., & Hunter, M. L. (2003, June). Can tooth brushing damage your health? Effects on oral and dental tissues. International Dental Journal. Elsevier BV.
  3. Pitchika, V., Pink, C., Völzke, H., Welk, A., Kocher, T., & Holtfreter, B. (2019, May 22). Long‐term impact of powered toothbrush on oral health: 11‐year cohort study. Journal of Clinical Periodontology. Wiley.
  4. Oral Health Topics | American Dental Association. The American Dental Association
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About the Author

Armaan Gvalani holds a Masters in Biotechnology from Symbiosis International University (India). He finds the microscopic world as fascinating as the business of biology. He loves to find practical applications from scientific research. When not peering into his microscope or nurturing his cultures, he can be found smashing a ball around the squash court or doing laps in a pool.