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Why Do I Have to Brush 

By Dr. Paul Nations, D.D.S, Cedar Bluff Dental

Untitled-17Children have a way of making adults consider questions that are usually taken for granted. Normal, everyday routines are interrupted with the persistent, “Why Daddy?” or “Why Mommy?” While it is tempting to deflect the conversation to another topic or introduce a well-timed distraction, considering what appears to be obvious and attempting to make things clear is far more constructive.

I can remember one of these times when my kids were younger. During our normal bedtime routine, my daughter asked the inevitable question, “Why do we have to brush our teeth, Daddy?” I did my best to explain the reason in a way that she could understand and with language she could relate to as a young child.

This was a great exercise for me as a dentist, and as I thought about it later, I wondered how many people really know the answer to this question. Of course, most people brush their teeth with some regularity, but do they truly understand what effect brushing has and what it actually prevents from happening, or do they simply brush because somebody told them to without explaining why?

Everyone, no matter how frequently they brush, has bacteria in their mouth. This is normal.

Here’s a brief and, hopefully, easy-to-understand answer to the question, “Why do I have to brush my teeth?” to share with children, relatives, or anybody challenging the wisdom of this important preventive routine.

Everyone, no matter how frequently they brush, has bacteria in their mouth. This is normal. Think of them as tiny little bugs living in the mouth. These bacteria build their little bug houses in the form a sticky white film that attaches to the teeth, which allows them to live and reproduce. Commonly, this film is known as plaque. These bacteria basically eat whatever we eat, but they especially like sugar. After eating sugary foods, the bacteria living in the plaque eat the sugar that stays in the unbrushed teeth.

Just as we eliminate waste after eating, so do the bacteria in the form of an acid. Now, one thing that we know about acids is that they dissolve things, and this is exactly the case with our teeth. Repeated contact with bacterial acid causes the hard coating of teeth, the tooth enamel, to break down, and this leads to cavities (or dental decay). If the plaque is not removed through frequent brushing, flossing and regular dental cleaning, it can harden and make teeth more and more difficult to clean. Not brushing teeth not only invites bacteria to build their house of plaque, it actually helps them build it!

Brushing teeth both removes food as well as the bacteria filled plaque that causes cavities. Regular brushing helps keep plaque from forming, limits the number of times the acid is allowed to come into contact with the teeth, and it reduces the amount of time the acid has to attack the teeth. Using a toothpaste with fluoride helps strengthen teeth by remineralizing enamel that has been damaged by bacteria, plus it kills the bacteria.

Because some foods like oranges, lemons, tomato-based foods, coffee, and soft drinks are, themselves, high in acid (1), be mindful of this fact when deciding to brush. Just like bacterial acid, eating or drinking something very acidic can cause the enamel to weaken. Once weakened, the enamel can actually be removed by vigorous brushing. Therefore, it is actually better to not brush right away after consuming acidic foods and drinks but to wait a bit before brushing. Another option is to brush before eating or drinking foods with a high acid content.

The Mayo Clinic offers the following recommendation from the American Dental Association (2):

Brush twice a day with a fluoride toothpaste.

Floss daily.

Drink plenty of water, eating a heathy diet and limiting between meal sugary snacks.

Replace toothbrushes every three months (or sooner if the bristles are frayed or bending).

Schedule regular dental checkups to clean teeth thoroughly and to catch any tooth decay before it becomes an even greater health risk.

So, why brush your teeth? Because, as small as they are, bacteria can cause a tremendous amount of damage. Ignoring this basic practice puts not only teeth at risk, but also general health.

1 Tosuni-O’Neill, D., RDH, BS. (n.d.). How Acidic Foods Affect Teeth and Which to Avoid. Retrieved May 16, 2016, from

2 Salinas, T. J., D.D.S. (2016, May 3). Adult health. Retrieved May 16, 2016, from

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