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Causes of Cavities | United Concordia

Common Dental Questions

Causes of Cavities



What causes cavities/tooth decay?



Cavities, or tooth decay, are caused by an infectious disease called caries. Caries is caused by certain types of bacteria that live in the mouth. Most types of bacteria that live in the mouth are good and help keep the mouth healthy. Some bacteria, however, are harmful and can cause damage to teeth, gums and bone. 


How do the bacteria in your mouth cause tooth decay?

The bacteria live in a sticky film, called plaque or biofilm, that continuously forms on teeth. These bacteria feed on sugars and starches in food particles (sugary and sticky foods can make your situation even worse). The harmful bacteria produce acids that soften the thin protective layer of your tooth, called enamel. Over time, a hole, or cavity, can form in the enamel.


What happens if I don’t see the dentist to get checked out?

Left untreated, a small area of decay on the tooth surface can penetrate deep into the tooth structure. Active decay in one tooth can spread to surrounding teeth. The bacteria that cause caries can also spread from one person to another through the exchange of saliva. Caries is the most common infectious childhood disease. Babies are born without harmful bacteria in their mouth, but they are typically infected by a parent or other caregiver by the age of two years.