5 Things You Need To Know About External Root Resorption

Root resorption is a process through which the cementum and dentin that make up the roots of your teeth are broken down and absorbed back into your body. External root resorption occurs when this process starts on the outside of the tooth root, rather than on the inside. Here are five things you need to know about external root resorption.

What are the signs of external root resorption?

The scary thing about external root resorption is that it doesn't usually cause any symptoms. Often, it can only be detected through x-rays, so your dentist may discover the condition during your yearly checkup.

Sometimes, this condition causes symptoms. Color changes in your teeth, like teeth turning grey or black, can be a clue that you have external root resorption, so any color changes should be evaluated by your dentist.

What causes it?

There are a few different causes of external root resorption. One major cause is trauma such as cracking or breaking a tooth. Orthodontic movement is another major cause; braces and other orthodontic treatments put a lot of pressure on the roots of your teeth over an extended period of time, and this pressure can lead to resorption.

Other dental problems like cysts, tumors, impacted teeth can also play a role in the development of external root resorption. These problems put pressure on the nearby teeth, just like orthodontic treatments do, and cause resorption for the same reason.

Can it lead to tooth loss?

External root resorption can lead to tooth loss if the condition is allowed to progress far enough. Resorption starts at the tip of your tooth root and progresses upwards. The bottom third of your root only provides about 10% of the support to your tooth, so losing it is not too serious. The middle third of your tooth provides about 30% of your tooth's support, but losing it still isn't devastating.

If only the top third of your tooth root remains in your mouth, your tooth will still have about 60% of its support and will be able to function as normal. It's only when this top third is lost or partially lost that you may lose your tooth, so as long as the condition is treated promptly, you should be able to keep your tooth.

How is it treated?

Root canal therapy is the generally the first treatment option for external root resorption. Root canal therapy is a simple and routine procedure. Your dentist will remove the pulp from the center of your tooth and fill the chambers with calcium hydroxide dressing, a paste that can stop resorption. This dressing will be changed on a regular schedule until your dentist is satisfied that the resorption has stopped. At that point, your pulp chambers will be filled with a permanent filling known as gutta percha. 

If your dentist thinks that orthodontic treatment is the cause of your resorption, you may need to pause your treatment until the resorption is under control. Your dentist may consult with your orthodontist to coordinate your treatment if this is the case.

After your treatment for resorption has been completed, your dentist may want to monitor your roots on a regular basis. This is done to make sure that the problem does not recur.

Is external root resorption common?

External root resorption is a fairly common dental problem. Between 1% and 5% of teeth show a loss of one-third of their root length as a result of this condition. It has been reported to be even more common among people who are undergoing orthodontic treatment. One study found that 14.5% of people who had undergone orthodontic treatment had the condition in their incisors.

If you have braces and are concerned about external root resorption, see your dentist.