The Bacteria in Your Mouth


Most people have about five hundred to one thousand different bacteria living in their mouths. It’s a normal part of human microbiology. People with clean teeth have somewhere between 1,000 to 100,000 bacteria living on each of their teeth. People with dirty mouths can have up to a billion bacteria per tooth.

Every day, bacteria are being created and dying in a person’s mouth. They are not all necessarily bad, but they do have a side effect on your mouth, as well as your entire body. If you wanted to discover unknown and unnamed bacteria, the mouth is a great place to start looking. Half the bacteria in your mouth are mostly unknown to science, and you also are able to share unique ones from your life with others.

These are the most common types of mouth bacteria:

Streptococcus mutans (S. mutans) and similar related species cause tooth decay. The bacteria digest

the sugars and starches in foods and produce acids which dissolve tooth enamel. They raise the pH of the mouth and there is a correlation of their presence and the presence of lactobacilli.

Lactobacilli, Streptococcus is the most common organism in the mouth. These organisms cause cavities, and transfer sugar into lactic acid which raises the pH level of our mouth.

Porphyromonas gingivalis are associated with periodontal (gum) diseases.

These are the main perpetrators. When you eat sugar, it is the Streptococcus mutans that raise the acidity of your mouth by producing an acidic byproduct. Porphyromonas gingivalis causes periodontal diseases such as the famous gingivitis. These two are the ones that we currently know have the largest impact on our health.

These bacteria make what we would call plaque, a soft deposit that appears on the teeth. Plaque is a complex microbiological community that is chalk full of bacteria. Inorganic material can also be found in the plaque, which is mostly calcium and phosphorus (which raises pH). Calculus is created when a large amount of this phosphorus by-product is created and hardens to the teeth. The benefits of dental cleanings are in that they help you remove this hard to lose calculus.

The topic of bacteria and your teeth is largely complex and hard to talk about. I have trouble absorbing the information, especially when most of the bacteria are entirely harmless. Even still, the main goal should be to have fewer bacteria compared to more. Clean mouths have fewer bacteria, and we encourage you to eat a proper diet and practice good dental habits to help limit the harm they could cause your mouth.

Interesting side note, it is the bacteria on our tongue that causes the majority of our bad breathe!