Tooth decay typically results when dental plaque accumulates on a person’s teeth. Plaque is a sticky film composed of a combination of bacteria, acid, food particles and saliva. The bacteria that accumulate on the teeth in dental plaque feed on all food particles found there – especially those from sugary or starchy foods – creating an acid that begins to destroy the enamel of teeth. The bacteria Streptococcus mutans are well known for their role in causing tooth decay.

Sugary and starchy foods and beverages, such as raisins, cakes, candy, soda, juice and milk, are the greatest contributors to the plaque that causes tooth decay. The acids contained in soda (e.g., phosphoric and citric acids) along with the sugar makes soda consumption a specific contributor to the development of tooth decay.

Plaque is most prevalent in the following regions:

• Around dental fillings and bridges
• Between teeth
• In cracks, pits and fissures of back teeth
• Near the gum line

Plaque begins to accumulate on teeth within 20 minutes of eating. Over time, plaque begins to dissolve minerals on the surface of the teeth. This process is known as demineralization, and it creates tiny pits and erosions that gradually become larger. When holes form in the teeth, they are known as cavities.

Damage can occur in any part of the tooth that is exposed to plaque, from the crown down to any portion of the root that is exposed due to recession of the gums. A cavity can also work its way deeper into the tooth and reach the softer body of the tooth (dentin). If left untreated, the decay eventually reaches the pulp of the tooth and the nerve fibers and blood vessels within the pulp. If the pulp becomes infected, a swelling (abscess) or opening to the surface of the gum (fistula) can form in the soft tissues.