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Biology 2nd Baccalaureate

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3.3.1. Diseases in the mouth

Diseases of the mouth


Bacteria live in the mouth that feed on the remains of food that remain between the teeth. They break down food and produce an acid that damages enamel, leaving cavities that can destroy the tooth.

The cavities can reach the pulp of the tooth and cause an infection with severe pain, resulting in a dental inflammation or abscess.

Cavities can be avoided if we brush our teeth after every meal. If tooth decay has already occurred, the dentist will need to do a filling. The dentist will remove the damaged part of the tooth and fill the gap with a substance to rebuild the tooth.

Answer in your notebook

3.17.- What is the cause of tooth decay?

Tartar and dental plaque

The dental plaque is a thin layer transparent and sticky that accumulates on the surface of teeth. It contains bacteria with food debris, sugar, saliva that dirties the teeth even if you have good dental hygiene, since bacteria are constantly formed. It is the leading cause of tooth decay  and other gum diseases.

To avoid dental plaque, it is necessary to brush and floss regularly. If it is not removed, it accumulates and mineralizes, hardening until it becomes tartar. Tartar can be seen because it gives a brown or yellowish color to the teeth. It is necessary to visit the dentist to remove it by cleaning the mouth.

The tartar, as well as pose a problem for healthy teeth and gums, it is an aesthetic problem, since the porous being, is easier than staining the teeth, especially if you smoke or drink coffee, tea, etc.

Sesame Street Song: Me and my llama.

Mouth cleaning

Do you fancy how a dentist performs a dental cleaning on a person who has a lot of tartar?

Gingivitis and pyorrhea

The gingivitis is a painful inflammation of the gums to become red and bleed. It is caused by dental plaque, so it is important to remove it with brushing.

If gingivitis is not treated, it can lead to pyorrhea. The piorrea or periodontitis not only affects the gum, but affected the bone that supports the tooth and may even disappear, with the consequent loss of teeth.


By Lesion (Own work) [CC BY-SA 3.0], via Wikimedia Commons


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