Your Tooth Is Dissolving — And You Didn’t Even Know
A patient came into our Torrance office a few months ago for a routine checkup. No pain. No swelling. Nothing felt wrong at all. Her general dentist had taken a regular X-ray and noticed something odd — a dark spot inside one of her upper front teeth. It looked like something was eating the tooth from the inside out.
Because that’s exactly what was happening.
Her body’s own cells were breaking down the tooth structure. Slowly. Silently. No warning signs. If her dentist hadn’t caught it on that X-ray, she wouldn’t have known until the tooth became weak enough to fracture or get infected.
This is tooth resorption. And it’s more common than most people think.
What Is Tooth Resorption?
Here’s the simplest way to explain it. Your body has cells called osteoclasts that are designed to break down and remodel bone. That’s a normal process. But sometimes these cells get confused and start attacking your tooth instead. They eat away at the root, the inner walls, or the neck of the tooth — depending on the type of resorption.
The tricky part? Most resorption causes zero symptoms in the early stages. No pain. No sensitivity. Nothing you’d notice on your own. It’s usually found by accident on a dental X-ray. And by the time symptoms show up — like a pinkish spot on the tooth or looseness — the damage can be pretty significant.
That’s why early detection changes everything.
The Four Types of Resorption
Not all resorption is the same. Where it starts and how it behaves determines the treatment. Dr. Phan sees all four types at our Torrance practice, and each one needs a different approach.
Internal Resorption
This is the one that starts inside the tooth. The cells lining the pulp chamber — the space where the nerve lives — start breaking down the walls of the tooth from within. On an X-ray it looks like a balloon-shaped dark area inside the root.
Sometimes you can actually see a pink spot on the tooth. That pink color is the inflamed tissue inside showing through the thinning tooth wall. Dentists call it a “pink tooth” and it’s a classic sign of internal resorption.
Internal resorption is almost always linked to some kind of trauma or long-term inflammation inside the tooth. It’s not super common, but when it happens, it needs treatment before it hollows out the root.
External Inflammatory Resorption
This type attacks the outside of the root. It’s often caused by infection, trauma, or pressure from things like impacted teeth or cysts. The body’s inflammatory response gets directed at the root surface, and those osteoclasts start chewing away at it.
You’ll see this sometimes after a tooth gets knocked hard — like from a fall or a sports injury. The root starts breaking down from the outside. On a regular X-ray, it can look like the root tip is getting shorter or ragged.
Cervical Resorption (Invasive)
This is the sneaky one. Cervical resorption starts right at the neck of the tooth — the area where the crown meets the root, just below the gum line. It burrows into the tooth from that spot and can spread in unpredictable patterns.
What makes cervical resorption different is how aggressively it can tunnel through the tooth. It can wrap around the root canal without actually entering it, creating a complex maze of damaged tissue. On a regular X-ray, it’s easy to miss or mistake for a cavity. A CBCT 3D scan is really the only way to see the full picture.
Causes include trauma, orthodontic treatment, bleaching procedures, and sometimes it just happens with no clear trigger. Patients across Torrance and the South Bay who had braces years ago are sometimes surprised when this shows up decades later.
Replacement Resorption (Ankylosis)
This one is different from the others. Instead of creating a hole, the body replaces the tooth root with bone. The root slowly fuses with the surrounding jawbone. The tooth loses its normal cushioning — the periodontal ligament — and becomes rigid and locked in place.
You’ll hear a distinct metallic “tink” when tapping on an ankylosed tooth. That sound is different from a normal tooth and it’s a quick diagnostic clue. Replacement resorption often happens after a tooth gets knocked out and reimplanted. The prognosis for this type is generally poor long-term, as the root will continue to be replaced by bone over time.
How CBCT Changes Everything
Here’s something that comes up again and again with resorption cases. A patient gets referred to our office after their dentist saw “something weird” on a regular X-ray. They know something is wrong, but they can’t tell exactly what type of resorption it is, how far it’s spread, or whether the tooth can be saved.
That’s because a regular dental X-ray is flat. It’s two-dimensional. It compresses all the structures on top of each other. A resorptive defect hiding on the tongue side of the root? A 2D X-ray might not show it at all.
Our CBCT scanner takes a full 3D image of the tooth and surrounding bone. Dr. Phan can rotate the tooth on screen, slice through it from any angle, and map exactly where the resorption is, how deep it goes, and whether it connects to the root canal.
For cervical resorption in particular, CBCT is a game-changer. These lesions spread in weird, irregular patterns that a flat X-ray simply can’t capture. Dr. Phan has seen cases where a 2D X-ray made a tooth look hopeless, but the CBCT showed the resorption was actually contained to one area — and the tooth was saveable.
The reverse happens too. Sometimes a 2D X-ray makes things look small, but the CBCT shows much more damage than expected. Either way, you need the full picture before making a treatment decision. That’s why every resorption case in our Torrance office gets a CBCT scan.
Treatment: What Can Be Done?
Treatment depends entirely on the type, location, and how much tooth structure is left. Here’s how Dr. Phan approaches each one.
Treating Internal Resorption
This one is the most straightforward. Since internal resorption is driven by the living tissue inside the tooth, a root canal stops it in its tracks. Remove the inflamed pulp tissue, clean and disinfect the canal, and fill it with biocompatible material. Once the source cells are gone, the resorption stops.
The key is catching it before it eats all the way through the root wall. If there’s still enough tooth structure left after the root canal, the tooth can last a long time. If the internal resorption has perforated through the side of the root, Dr. Phan may need to repair the hole with MTA — a biocompatible cement that seals the defect and encourages healing.
Treating External Inflammatory Resorption
The first step is treating whatever is causing the inflammation. If there’s an infection, root canal therapy addresses it. If there’s pressure from an impacted tooth, that needs to be dealt with by the oral surgeon.
In some cases, Dr. Phan combines root canal treatment with a small surgical procedure. He’ll access the damaged area of the root from the outside, clean out the resorptive tissue, and repair the root surface. Medication like calcium hydroxide may be placed inside the canal for a period of time to help calm things down before the final fill.
Treating Cervical Resorption
This is where things get more complex. Cervical resorption often requires a combined approach — sometimes a root canal, sometimes surgery, sometimes both, sometimes just surgical repair without touching the canal at all.
Dr. Phan uses the CBCT to plan the surgery like a roadmap. He knows exactly where the resorptive tissue is before he ever picks up an instrument. During the procedure, the damaged tissue is carefully removed under microscope magnification, and the defect is repaired with biocompatible materials like MTA or a glass ionomer cement.
The results can be really good when cervical resorption is caught early. But if more than about a third of the root circumference is gone, the prognosis starts to drop. Dr. Phan is honest about this. He’d rather give you a realistic picture than promise something the tooth can’t deliver.
Managing Replacement Resorption
There’s no way to stop replacement resorption once it starts. The root will continue to be replaced by bone over time. The question becomes: how long will the tooth last, and what’s the plan when it eventually fails?
For younger patients who are still growing, the ankylosed tooth can cause problems because it won’t move with the surrounding bone as the jaw develops. For adults, the tooth might function fine for years — even decades — before it needs to be replaced with an implant.
Dr. Phan monitors these cases with regular CBCT scans and helps patients plan ahead.
When Can a Tooth Be Saved — And When Can’t It?
Dr. Phan gives it to you straight. Here’s the honest breakdown.
Good chances of saving the tooth:
- Internal resorption caught before it perforates the root
- External inflammatory resorption with a treatable cause
- Cervical resorption that’s limited in size and caught early
- Enough healthy tooth structure remaining to support a restoration
Tougher prognosis:
- Resorption that’s destroyed more than a third of the root
- Cervical resorption that wraps around most of the tooth
- Replacement resorption (can be monitored but not reversed)
- Perforations in areas that can’t be sealed
Sometimes the kindest thing is an honest conversation about extraction. A tooth that’s going to fail in six months isn’t worth putting you through an expensive treatment. When extraction is the better path, Dr. Phan will say so — and help you plan for an implant or bridge with your general dentist.
But a lot of teeth that look hopeless on a regular X-ray turn out to be treatable once you see the CBCT. That’s why getting the right imaging before making a decision is so important.
Why Early Detection Matters So Much
Resorption doesn’t wait around. Internal resorption can hollow out a root in months. Cervical resorption can spread fast once it gets going. The earlier you catch it, the more tooth structure remains, and the better the odds of saving it.
This is one of those conditions where regular dental checkups actually save teeth. Your general dentist takes routine X-rays. They spot something that doesn’t look right. They send you to a specialist. And Dr. Phan catches it while there’s still plenty of tooth left to work with.
If you’re a patient in Torrance, Redondo Beach, Manhattan Beach, Hermosa Beach, Palos Verdes, or anywhere in the South Bay — keep up with your regular dental visits. Resorption is almost always silent until it’s advanced.
Schedule Your Evaluation
If your dentist spotted something unusual on your X-ray, or if you’ve been told you have resorption and want a second opinion, call our Torrance office or contact us online to schedule an appointment. Dr. Phan will take a CBCT scan, show you exactly what’s going on, and give you an honest recommendation about whether treatment makes sense for your tooth.
The sooner we see it, the more we can do about it.