3 mins read

What Happens When Cavities Go Unfilled

by | Jul 9, 2019

According to the NIH, more than 90 percent of adults will get a cavity, also called dental caries, at least once in their lifetime. About 26 percent of individuals between the ages of 20 and 64 will have at least one unfilled cavity. 

Many Americans question how long they can leave a cavity untreated. However, an unfilled cavity shouldn’t be left untreated very long due to the risk for infections, abscesses, and increased tooth decay pain.

How Cavities Happen

Cavities happen when food particles are left on the teeth for an extended period of time. Your mouth is home to millions of good and bad bacteria colonies. Leftover food particles, especially those from sugary or acidic foods, create the perfect, acidic breeding ground for bad bacteria. As the bacteria grow and multiply, your tooth enamel suffers damage from the acid created by the bacteria. Once there is a hole in the enamel and the bacteria can enter the tooth, a cavity is created.

Symptoms of Cavities

The most common symptoms of a cavity that many individuals experience include:

  • Tooth decay pain, toothaches, or general tooth pain
  • Pain when chewing or biting down
  • Bad breath
  • Pain when drinking hot or cold liquids
  • Swelling or inflammation around the tooth (could be an abscess)
  • Visible holes, pits, or black/brown spots on your teeth

What Happens When an Unfilled Cavity is Left Untreated

The most common reason dentists hear from their patients not getting their cavities filled is that they were unaware they had developed a cavity. Some individuals don’t even realize they have a cavity until they’re sitting in a dentist’s chair which is typically only every six months for a bi-annual cleaning. This is because small, early developed cavities don’t typically cause the pain that patients typically associate with tooth decay. 

Many adults wonder, do small cavities need to be filled? The short answer is yes and no, as it depends on a variety of factors. If the cavity is extremely small, filling it may not be ideal. Instead, your dentist may recommend fluoride treatments or preventative resins, also called sealants, in order to prevent the cavity from becoming any worse

Large Fillings and Root Canals

When cavities aren’t filled in a timely manner, it can result in some pretty serious consequences. In fact, the best scenario that occurs when a cavity has been left to worsen is a very large filling. However, if there isn’t enough tooth material left, a large cavity can result in the need for a root canal. A root canal involves the removal of the pulp and soft tissues inside the tooth. Then, the resulting void is filled and sealed to prevent further damage to the tooth. In some instances, a crown may be placed over the tooth to further protect it and restore its function. Large fillings, and especially root canals, are pricey compared to the low cost of a small cavity filling. 


Abscesses, which are serious infections, can also form in a tooth that is severely decayed. Abscesses can cause serious pain and swelling as the decay worsens. It’s important to understand that an abscess is a serious, potentially life-threatening infection that can infect the surrounding oral tissues and even the bone. If you are having extreme oral pain and/or notice pus draining from a pimple-like formation on your gums, it is extremely important to see your dentist right away. 

Dental Implants

In some instances, the damage to the tooth is so severe that fillings and root canals aren’t recommended. In these instances, the diseased tooth may need to be completely extracted. This can result in the need for a dental implant, which consists of a post and a crown. The post is inserted into the gum and bone. Once the tissue has healed and fused around the post, a crown is attached, which fills the gap left by the extracted tooth. Dental implants look and function just like natural teeth, but like root canals and large fillings, can be costly if they are unexpected.


While cavities are common, they should still be taken seriously. Tooth decay is completely preventable with a proper oral hygiene routine, healthy diet, and regular visits to your dentist. When you leave cavities untreated, not only are you putting the health of your smile at risk, but you are also asking for added expenses from root canals or dental implants if the cavity continues to develop. If you have a cavity, make an appointment with your dentist as soon as possible for a filling


Triangle Dentistry, located in Raleigh, NC, provides a state-of-the-art facility that offers exceptional general dental and specialty services guided by empathy of a patient’s needs and desires. Services range from dental crowns to veneers and whitening procedures. For further information, questions, or to schedule an appointment, contact the office at (919) 747-3608.