Resorption is when the body’s own cells break down part of a tooth. The process is uncommon, usually silent in the early stages, and often found on routine dental X-rays or a scan rather than because of symptoms.
Teeth are living structures. The same kinds of cells that remodel bone can start to break down tooth tissue instead.
That process is called resorption, and can begin inside the tooth or on the outer surface of the root.
Internal resorption starts within the root canal system. External resorption starts on the outside of the root.
Both tend to be silent early on. Most cases are picked up on a routine X-ray rather than because anything feels different.
This is the type most often seen after a knock to a tooth, or alongside long-standing infection or a crack.
Inflammation around the root switches on cells that remove tooth structure. Without treatment, the area involved tends to enlarge.
One pattern has a character of its own: external cervical resorption, which begins at the neck of the tooth close to the gum line and is often found years after a knock. More about external cervical resorption →
A standard X-ray is a flat picture of a three-dimensional situation. A flat image can show that something is there without showing how far the resorption has reached.
A CBCT scan shows the area in three dimensions. That is often what settles whether a tooth is treatable.
The dose is kept low and the scan is limited to the area of interest. A scan is taken only where the extra detail will change how the tooth is treated. More about CBCT scans in endodontics →
Where inflammation inside the tooth is driving the process, root canal treatment removes what is feeding the resorption.
The tooth is then restored, usually with a crown on a back tooth. Where resorption is very advanced, keeping the tooth may not be realistic, and that is discussed openly.
Finding resorption does not by itself decide the future of a tooth. A diagnosis of resorption means the tooth needs assessing properly, and usually treating sooner rather than later.
Some teeth matter more than others. Where a tooth is carrying most of the chewing, keeping the tooth in service can be worth more than its textbook prognosis.
External inflammatory resorption confirmed on a CBCT scan, in a tooth that mattered more than its prognosis suggested.