What are caries?

Caries refer to the hole that forms inside the tooth as a result of loss of decayed dental tissue. This occurs when specific types of bacteria produce acid that destroys the enamel of the tooth and its underlying layer, dentin.

Signs and Symptoms

There are three signs that indicate the presence of cavities: localized pain in the affected teeth, dental sensitivity to hot or cold drinks and pain while chewing. If you notice any signs of dental decay, visit a dental professional immediately.


Many different types of bacteria live in our mouth and accumulate in our teeth in a sticky film called dental plaque. At every meal, the bacteria’s acid removes minerals from the enamel, so they can cause tooth decay if left untreated. The decay begins in the main part of the tooth (enamel) and as the enamel decomposes, the decay goes deeper into the dentin until finally, reaching the nerve (pulp) of the tooth.


Your dentist can diagnose decay by examining the surface of the tooth and taking an x-ray to see if it extends to the dentin or pulp of the tooth.


Several ways to prevent cavities include:

  • Brushing and flossing daily; this helps reduce the amount of dental plaque and bacteria in the mouth.
  • Moderate consumption of sugary or starchy foods to reduce the amount of acids that damage teeth in the mouth.
  • The use of fluoride toothpaste, which strengthens the teeth, as well as treatments provided by the dentist.
  • The use of antibacterial mouthwashes to reduce the levels of bacteria that cause cavities.


In adults, dentists can apply sealants on molars that have the first signs of tooth decay, as long as the decay has not destroyed the enamel. Once the enamel has been irreversibly compromised, your dentist will have to seal the tooth. In more severe cases, root canal therapy (endodontics) may be necessary.
In children, the two baby molars and permanent molars can be sealed. Dentists can also apply fluoride varnish to both primary and permanent teeth to protect against tooth decay.


Untreated caries causes the tooth to decay significantly and can be completely destroyed. There is also the risk of developing an infection related to an abscess when the infection spreads to the root of the tooth.