In dental school, we were taught that the reason why we develop decay is: Sugar + Bacteria = Acid and then Acid + Tooth= Decay. Now, this is definitely true but doesn’t explain how bacteria and sugar can create decay when they combine. Isn’t it baffling how some people can eat a lot of sugar and survive a lifetime with no decay whereas some eat little sugar and have a lot of cavities?
The answer? Bacterial balance.
Our mouth is in a permanent partnership with bacteria, which help to maintain our teeth and gums. We have always associated plaque as the bad guy, but in-fact plaque helps to maintain our teeth. The mouth has it really rough, it’s a hard place to live, with us chewing, talking and breathing. So to survive this harsh environment microbes build little houses- plaque biofilms, to protect themselves.
When you eat, your salivary glands add enzymes to your saliva to start the process of digestion, which decreases the PH of your mouth. When your mouth is slightly acidic, calcium and phosphorous ions are pulled out of the enamel and into saliva. When your mouth is healthy, bacteria help to manage this exchange. In order for bacteria to survive and build their little plaque houses they need calcium too, so they share the calcium in our saliva with our teeth.
So in a happy mouth, you need the microbes inside the mouth to be in harmony. Saliva gives the bacteria/microbiomes the minerals they need to build their houses, and in exchange, the microbes help supply minerals that pass among your saliva, biofilm and tooth enamel. Everyone’s happy.
In the mouth there are 2 types of bacteria:
- Slow eaters (good guys)
- Fast eaters (not so good guys)
The fast eaters feed on refined sugars, white flours. When we eat these foods the bacteria go into frenzy mode and when they digest these sugars they release acids. These acids pull calcium out of the tooth. The microbes counterbalance this by releasing calcium from saliva and the plaque biofilm.
Having too much sugar the fast eating guys multiple and produce too much acid. The microbes run out of calcium from saliva and the biofilm reserves and the only place left is the bacteria eating the enamel, and bam! there’s tooth decay.
It’s the fact that too much sugar sparks a chain reaction, which leads to too much calcium leaching out from the enamel too quickly. The modernisation of food is actually disrupting the bacterial balance and bingo, here we have dental disease.