What Is Tooth Resorption?

Tooth resorption is not a common occurrence. But it does happen from time to time. 

It is when the immune system breaks down the tooth, essentially eating away at it. This causes it to be non-restorable and requires extraction. 

Resorption can occur in both adult and primary (baby) teeth, but it is normal and not usually harmful when it occurs in baby teeth. Without the normal resorption of baby teeth, they cannot easily fall out and make space for adult teeth to erupt. 

Tooth resorption can occur in three ways: internal resorption, external resorption, or a combination of the two. 

External Resorption 

External resorption occurs from the outside of the tooth, where the cementum is located. 

It is common and has three main classifications (depending on the appearance of the x-ray and clinical symptoms).

1. Inflammatory external resorption is when there is chronic resorption that usually takes place after trauma or surgery.
2. Surface external resorption is usually limited to the root surface and a transient condition that can heal on its own. 
3. Cervical external resorption is located at the cervical area of the tooth, rarely affecting the pulp. It usually occurs from prolonged trauma to the tooth. 

Internal Respiration 

Internal resorption is much less prevalent than external resorption and occurs from the inside of the tooth. 

It is typically asymptomatic, and most patients are unaware of the condition until an x-ray is taken. It occurs from blunt trauma or from a previously done deep filling that irritates the nerve. 

An x-ray will show dark spots from inside the tooth near the pulp where the resorption takes place. 

What Causes Tooth Resorption?

There are numerous causes of resorption, but the most common occurs after a trauma or dental surgery. 

Other causes could be related to chronic teeth grinding. Patients who consistently bleach their teeth with teeth whitening products may experience resorption.

Rapid orthodontic treatment is a common cause of external tooth resorption because of quick tooth movement instead of steady, slower tooth movement. It causes forces that result in harmful root resorption.

Internal resorption is usually caused by an untreated cavity or a chronic dental abscess that eats away from the inside of the tooth. 

According to the American Association of Endodontics, the location of trauma (or damage to the tooth) and its supporting structures determine the type of resorption taking place. 

What are the Symptoms of Tooth Resorption? 

Most people are completely unaware that they have tooth resorption until it becomes a severe condition. 

Resorption is usually diagnosed when darker spots are found on a radiograph during a routine x-ray.

When resorption becomes more severe, it may cause some clinical symptoms like gum problems, loose teeth, or pain. 

Is Dental Resorption Painful?

Many patients don’t report pain when they are diagnosed with tooth resorption. It depends on the severity and the location of the resorption. 

For example, if the resorption is located near the root surface, some patients notice sensitivity. 

Other common symptoms of resorption include: 

• Brittle and loose teeth
• Holes in the teeth
• Unusual spaces between teeth
• Gum inflammation
• Pain all around the tooth or root

How to Manage Tooth Resorption

Tooth resorption is managed by preserving the parts of the tooth that are affected. 

If resorption is caused by an external factor, sometimes treatment is needed. This may include a nightguard or removing an orthodontic appliance. 

Depending on the severity of resorption, there are several types of dental treatment available to preserve the tooth, including:

• Root canal treatment
• Gum surgery
• Tooth extraction and replacement with a dental implant 

For younger teeth with immature roots, endodontists can place calcium hydroxide to limit the amount of root resorption. The goal is to stop the progression of root resorption and allow it to continue to form normally.

If the root is completely formed, it usually requires a surgical endodontic procedure to remove harmful, damaged cells so the resorption does not continue. 

For teeth that show early resorption, sometimes a dentist will perform a small surgery to remove the damaged cells. For more severe cases, a root canal and crown can help preserve the natural tooth.

The most severe cases are those that are non-restorable and can cause a potential infection and pain. A dentist will typically extract the tooth. 

When to See a Doctor

You should visit your dentist at least twice a year. You’ll receive a professional cleaning, a comprehensive dental examination, a thorough head and neck exam, and any necessary x-rays.

If your dentist notices any signs of tooth resorption, they may want to see you sooner for follow-ups and monitor the tooth for any changes. 

How is it Diagnosed?

Tooth resorption is diagnosed through dental x-rays and a clinical examination.

X-rays like bitewings or periapical radiographs can be used to diagnose tooth resorption.

Sometimes it is difficult to determine the type of resorption. This can impact the treatment and course of action. In these cases, a 3D Cone Beam x-ray will be used to get a better visual of the condition.

A clinical exam for external resorption may include a visual inspection or both a visual and an endodontic examination. This exam uses hot and cold temperature changes to examine the tooth.

How to Prevent Resorption of Teeth 

The best way to prevent any tooth injury or damage is to protect them. You can do this by brushing and flossing regularly and maintaining a healthy diet to avoid tooth decay.

If you play any contact sports, wear a mouthguard to prevent trauma. If you grind your teeth, talk to your dentist about a night guard to help limit clenching and damage. 

Most importantly, visit your dentist for routine visits so x-rays and proper clinical examinations can be performed. This way, if tooth resorption is diagnosed, it can be managed to avoid long-term dental problems.