Dental caries, or cavities, are very common. They are caused by acid on the tooth. The acid is made from the bacteria in dental plaque. The plaque bacteria feed on sugars and starches from the diet and change them into acid. This acid eats into tooth enamel, or the outer layer of the tooth, and dentin, the major part or core of the tooth. The tooth then gradually dissolves.

What is going on in the body?

Plaque is a bacterial mass and it sticks everywhere on the teeth. It is especially hard to remove from the grooves of the teeth, between the teeth, and around the gumline of the teeth. Fillings, crowns, dentures, partials, orthodontic bands, and retainers make good hiding places for bacteria. Brushing and flossing are important in preventing cavities.

Once acid works its way through the tiny cracks in the enamel, it reaches into the dentin, where it spreads more quickly. In time, the acid reaches the nerves and blood vessels in the center of the tooth, called the pulp. When this happens, the harmful products of the bacteria infect the pulp and a tooth abscess, or pocket of pus, soon follows. This can happen with very little warning since the bacterial attack is so gradual that there may be no pain or sensitivity until the cavity is quite large.

What are the causes and risks of the disease?

There is no way to predict how fast the decay process will eat through the tooth structure and damage the blood vessels and nerve fibers within the pulp of the tooth. When this happens, the tooth will become infected and an abscess may form.

The sooner a cavity is found, the simpler the treatment.