An extra tooth is a real dental condition called hyperdontia, and it’s more common than most people realize. Roughly 2 to 3% of the population develops at least one extra tooth beyond the normal 20 baby teeth or 32 adult teeth. The extra tooth can show up anywhere in your mouth, though it most often appears between your two upper front teeth, behind your molars, or alongside them.
What Causes an Extra Tooth to Grow
The short answer is that the cells responsible for building your teeth became overactive during development. Your teeth form from a strip of tissue called the dental lamina, which acts like a blueprint telling your jaw where to grow each tooth. Sometimes this tissue produces more tooth buds than it should, and those extra buds develop into fully formed (or partially formed) teeth.
Why those cells go into overdrive isn’t completely understood, but several factors play a role. Genetics is the biggest one. If a parent or sibling had an extra tooth, your chances go up. There’s also an evolutionary theory: our distant ancestors likely needed more teeth to grind raw plants and nuts, and occasionally that old genetic programming reactivates. This phenomenon, where a trait from deep in your ancestry resurfaces, is called atavism.
Males are roughly twice as likely to develop extra teeth as females. One large study of over 7,500 patients found a male-to-female ratio of about 1.8 to 1, and another study of 3,000 children put that ratio even higher at 2.3 to 1. No one has pinpointed exactly why sex matters here, but the pattern is consistent across populations worldwide.
Types Based on Location and Shape
Extra teeth are categorized by where they appear and what they look like. The most common type is a mesiodens, a small, peg-shaped tooth that grows between your upper front teeth. It’s the one most people notice because it can push your front teeth apart or block a permanent tooth from coming in.
Extra teeth near your premolars (the teeth between your canines and molars) are called paramolars, while those that grow behind your last molar are called distomolars. Some extra teeth look almost identical to normal teeth, while others are small, cone-shaped, or lumpy and irregular. The shape matters because it often predicts whether the tooth will erupt through the gum on its own or stay buried in the jawbone.
When an Extra Tooth Signals Something Bigger
Most people with an extra tooth have no underlying condition. It’s an isolated quirk of dental development. However, in a small number of cases, extra teeth are one feature of a broader genetic syndrome. Conditions like cleidocranial dysplasia (which affects bone development throughout the body) and Gardner syndrome (which involves growths in the colon and other tissues) are known to include multiple extra teeth as a hallmark sign. If your dentist finds several extra teeth rather than just one, they may want to investigate further.
Problems an Extra Tooth Can Cause
An extra tooth isn’t always harmless. The most common issue is crowding. The extra tooth takes up space your normal teeth need, pushing them out of alignment or preventing them from erupting at all. In children, a mesiodens can block adult front teeth from coming in on schedule, and the longer it stays, the more likely it is to cause permanent spacing problems.
Other potential complications include root damage to neighboring teeth. The extra tooth can press against adjacent roots, gradually wearing them down or cutting off their blood supply. In rarer cases, a fluid-filled sac called a dentigerous cyst can form around the crown of an extra tooth that’s trapped in the jawbone. These cysts aren’t typically dangerous on their own, but if left untreated they can grow large enough to weaken the jawbone, shift surrounding teeth, or lead to infection and tooth loss.
How Dentists Find and Assess Extra Teeth
Sometimes you can see or feel the extra tooth yourself, but many extra teeth never break through the gum. They sit hidden inside the jawbone and only show up on an X-ray, which is why routine dental imaging is so important. A standard panoramic X-ray (the wide shot that captures your entire jaw) is usually the first tool dentists use to spot them.
If the panoramic image raises questions about exactly where the tooth sits, how it’s oriented, or whether it’s close to nerves or the roots of other teeth, your dentist may order a cone-beam CT scan. This produces a detailed 3D image that shows the tooth’s precise position and shape, which is especially useful for planning removal if the tooth is deeply impacted or positioned at an unusual angle.
When Removal Is Recommended
Not every extra tooth needs to come out. If the tooth is small, positioned high in the jawbone away from other tooth roots, and not causing any visible complications, your dentist may simply monitor it with periodic X-rays. This watch-and-wait approach is especially common in young children when the extra tooth develops alongside the baby teeth and isn’t interfering with anything.
Removal is recommended when the extra tooth is actively causing problems: blocking a permanent tooth from erupting, displacing neighboring teeth, creating a visible gap between the front teeth, causing root damage, or showing signs of cyst formation. In children, the timing depends on what’s happening around the extra tooth. If it’s preventing upper front teeth from coming in, early removal (often before age six) gives those teeth the best chance of erupting on their own. If the front teeth have already come in but are displaced, dentists sometimes wait until the lateral incisors (the teeth on either side of the front two) have erupted, then remove the extra tooth and use braces to correct the alignment.
After removal, if a blocked permanent tooth still hasn’t erupted within about six months, a dentist may surgically expose it to help guide it into place.
What Recovery Looks Like
If your extra tooth has erupted through the gum, removal is a straightforward extraction similar to any other tooth pull. If it’s impacted (stuck in the bone), the procedure is more involved and may require a small surgical opening in the gum and bone.
Either way, the typical healing period is about a week. Most people need one to three days off from work or school. The most important part of recovery is protecting the blood clot that forms in the empty socket. That clot is what allows the tissue to heal, and losing it can lead to a painful complication called dry socket. For the first 24 hours, avoid rinsing your mouth, using straws, or spitting, since all of these create pressure that can dislodge the clot. After that first day, gentle saltwater rinses can help keep the area clean.
Cold compresses on the outside of your cheek for 15 minutes at a time help with swelling and pain. Sleeping with your head slightly elevated on extra pillows also reduces swelling. Most people return to their normal diet and routine within a week, though more complex surgical removals can take longer to fully heal.