What Causes Cavities? 

It’s estimated that approximately 91% of Americans over 20 years of age have had cavities at some point. In addition to this staggering statistic, nearly 30% of Americans over 20 have untreated cavities. These numbers are incredible given the fact that with preventive care most cavities can be avoided. So how exactly does a cavity start?

Cavity in a premolar tooth.

The outer layer of a tooth is covered in enamel, this is the strongest substance in the human body but it can be eroded by acid. When we eat sugary foods, the cavity-causing bacteria in our mouths feed on the sugar as well. As a result they produce acid, which over time wears away the enamel and creates a cavity. This is why removing as much plaque as possible each day is imperative to preventing cavities. There are many factors that increase the risk for developing cavities. These include but are not limited to: 

  • A high sugar diet
  • Poor home care
  • Xerostomia (dry mouth)
  • Low exposure to fluoride
  • Frequent snacking
  • GERD
  • History of cavities
  • Eating disorders
  • Lack of dental care

A cavity often begins with a hyper-white and chalky or brown appearance, this is called demineralization. At this stage, before a true cavity is formed, the enamel can be remineralized with increased fluoride and good homecare. Once the cavity has progressed through the enamel and into the softer layer of tooth (Dentin) it cannot be reversed and will begin to progress more quickly. If the cavity is not filled, the decay will eventually reach the pulp chamber of the tooth. This is where the nerve and blood vessels of the tooth lie. If the decay infects the nerve a root canal is required to save the tooth. After a root canal a crown is indicated to provide strength to the tooth and prevent it from fracturing.

Chances are you’ve had a cavity or two filled in your life, but by identifying your risk factors with your dentist and hygienist we can formulate a plan to prevent future cavities. If you start to see or feel any signs of a cavity please call us! The sooner we can treat a cavity the better the prognosis and we can then determine what steps can be taken to prevent new cavities from developing. 


Dental Care

Mouth Healthy

National Institute of Dental and Craniofacial Research

American Dental Association

Leave a Comment