Why do I keep getting Cavities?

Many patients are frustrated when they brush and floss daily, eat a low sugar, low acid diet, and yet still get cavities. In this post I’ll discuss the modern concept of bacterial susceptibility.

To form a cavity, you must have 3 key things:

  1. Bacteria on your teeth (plaque) that can make acid
  2. Acid made by bacteria that pulls mineral out of teeth (food can also provide acid)
  3. Sugar to feed the bacteria


Many people are quite successful at eliminating acid and sugar, as well as cleaning as many bacteria as possible off their teeth. However, sometimes this isn’t enough. These patients are known as Caries Susceptible and their problem can’t be treated with toothbrush, floss, or a restricted diet.


We often inherit our bacterial strains from one of our parents or partners, and depending on your luck, you may have inherited a ‘good’ strain or a ‘bad’ one.


The key to understanding susceptibility is to know that bacteria aren’t all created equally. While we all have the same species of bacteria living in our mouths, some of us have strains  or “family types” of bacteria that are stronger acid producers than others. These super-acidic bacteria also happen to love living in acid, so tend to flourish and multiply rapidly in the right environment…one that they are creating for themselves as they make acid.  As more acid-loving bacteria appear, more acid is made…and a vicious cycle ensues.


The intervention in these cases centers on 2 critical points:


  1. Lower the acidity in the mouth
  2. Eliminate the acid-loving bacteria and promote colonization by less harmful bacteria that flourish in more neutral (non-acidic or basic) environments


In these cases, I prescribe a series of different prescription-strength mouth rinses and toothpastes that manipulate oral bacterial populations. The end result is that your mouth:


-Becomes less acidic

-Has fewer bacteria

-Has bacteria that make less acid


Feel free to ask us more about this. We’re passionate about helping our patients get better and stay better.

Call us when you’re ready for a different kind of dentistry: Risk-reducing dentistry helping you stay healthy for life.