Illustrations: How a Tooth Decays


1. Healthy Tooth


2. White Spots

Enamel is the hard outer crystal-like layer. Dentin is the softer layer beneath the enamel. The pulp chamber contains nerves and blood vessels. It is considered the living part of the tooth.

Bacteria that are exposed to sugars or carbohydrates can make acid. The acid attacks the crystal-like substance in the tooth's outer surface. This process is known as demineralization. The first sign of this is a chalky white spot. At this stage, the decay process can be reversed. Using fluorides at home and in the dental office can help the tooth repair itself.

3. Enamel Decay


4. Dentin Decay


Demineralization continues. Enamel starts to break down. Once the enamel surface is broken, the tooth can no longer repair itself. The cavity has to be cleaned and restored by a dentist.

The decay reaches into the dentin, where it can spread and undermine the enamel.

5. Pulp Involvement

Pulp Involvement

If decay is left untreated, it will reach the tooth's pulp. This is where the tooth's nerves and blood vessels are found. The pulp becomes infected. An abscess (swelling) or a fistula (opening to the surface of the gum) can form in the soft tissues.

Illustrations created by Simple Steps designer Lynda Buchhalter


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Look after your teeth, help prevent cavities

Bacteria that live in your mouth can stick to your teeth cause cavities. Use one of our fluoride toothpastes to prevent cavities.