Cavities refer to tooth decay, which occurs when specific types of bacteria produce acid that destroys your tooth’s enamel and its underlying layer, the dentin.

Signs & Symptoms

Three possible indications that you have a cavity are toothache, tooth sensitivity to sweet, hot or cold foods or drinks, or pain when chewing.


Many different types of bacteria live in our mouths and builds up on the teeth in a sticky film called dental plaque. When we eat and drink, these bacteria create acids, which can dissolve the protective layer beneath the retained plaque. The acid removes minerals from the enamel, which if left untreated can cause a cavity. Decay begins in the main portion of the tooth (the enamel) and as the enamel is broken down the decay goes deeper into the dentin and can eventually reach the nerve (pulp) of the tooth.


Your dentist can diagnose cavities by examining the tooth surface and by taking an x-ray to see if the cavity has gone from the enamel into the dentin or pulp of your tooth.


There are a variety of ways in which you can prevent cavities, these include:

  • Brushing and flossing daily; this will help reduce the amount of dental plaque and bacteria in your mouth.
  • Eating sugary or starchy foods less often during the day to help reduce the amount of tooth-damaging acids in your mouth.
  • Use of fluoride toothpaste, which strengthens teeth, as well as fluoride treatments provided by the dentist or taking fluoride supplements as recommended by the dentist.
  • Using antibacterial mouth rinses to reduce the levels of bacteria that cause cavities.
  • Chewing gum that contains xylitol; this can help decrease bacterial growth.


In adults, dentists can apply sealants on molars that have early signs of tooth decay, as long as the decay has not broken through the enamel. Once the enamel has been irreversibly compromised, your dentist will have to fill the tooth. In more serious cases, a root canal may be necessary.

In children, both baby molars and permanent molars can be sealed. Dentists can also apply fluoride varnish on both primary and permanent teeth to protect them from decay.


Did you know? If a cavity is left untreated then it can cause the tooth to decay significantly. Eventually, uncontrolled decay may destroy the tooth completely. There is also the risk of developing an infection related to an abscess when the infection spreads to the root of the tooth.

Related Conditions

Cavities are a result of poor oral hygiene and retained dental plaque on the tooth surface. Specific bacteria in plaque cause decay. Different types of bacteria in plaque, retained near the gum line, cause gum disease to occur, which is a condition that your dentist and periodontist can help treat. Because cavities can penetrate deep into the tooth structure as far as the nerve, you may also experience sensitivity with certain foods and drinks.

Other Information about Cavities

 Look after your teeth, help prevent cavities

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

Don’t brush off your oral health

Brushing your teeth twice a day will help keep your smile healthy.