For many people, nothing bad happens at all. About 37% of adults have at least one impacted wisdom tooth, and while impaction raises the risk of several dental problems, it doesn’t guarantee them. The real answer depends on whether your wisdom teeth are fully erupted, partially erupted, or trapped beneath the gum line, and whether they’re currently healthy or already showing early signs of trouble.
The American Association of Oral and Maxillofacial Surgeons puts it this way: wisdom teeth associated with disease or at high risk of developing disease should be surgically managed, but in the absence of disease, active monitoring is a reasonable choice. Some people keep their wisdom teeth for life without ever having a problem.
Pericoronitis: The Most Common Problem
When a wisdom tooth only partially breaks through the gum, a flap of tissue called an operculum can form over part of the tooth’s crown. Food, bacteria, and debris get trapped underneath that flap, and the result is an infection called pericoronitis. This is one of the most frequent reasons people end up needing their wisdom teeth removed after initially keeping them.
Chronic pericoronitis tends to be mild: a dull ache near the back teeth, bad breath, and an unpleasant taste that comes and goes. Acute pericoronitis is a different experience. It can cause severe pain, swollen and red gums, pus drainage, difficulty swallowing, facial swelling, swollen lymph nodes in the neck, and even lockjaw (difficulty opening your mouth). Some people develop a fever. These episodes can recur, and each recurrence increases the likelihood that extraction becomes necessary.
Damage to the Teeth Next Door
An impacted wisdom tooth doesn’t just sit there passively. If it’s angled toward the neighboring molar (called a mesioangular impaction, and it’s the most common type), it can press against that tooth’s root over months or years. This pressure can cause external root resorption, where the root surface of the adjacent molar is slowly eaten away. The process often produces no symptoms until the damage is significant.
In one documented case published in the British Dental Journal, a patient developed intense, localized pain in a back molar. The tooth’s crown looked perfectly healthy with no visible decay, but imaging and surgery revealed that an impacted wisdom tooth had caused a cavitated resorptive defect on the neighboring molar’s root. That molar had to be extracted. The takeaway: an impacted wisdom tooth can silently destroy a tooth you actually need for chewing, and by the time you feel pain, the damage may be irreversible.
Impacted wisdom teeth also create hard-to-clean pockets between themselves and the second molar. Bacteria thrive in these spaces, increasing the risk of cavities on the back surface of the adjacent tooth and periodontal (gum) disease in that area.
Cysts and, Rarely, Tumors
Every unerupted tooth sits inside a small sac of tissue called a follicle. Normally the follicular space around the tooth is just a few millimeters. But fluid can accumulate between the remnants of the tissue that helped form the tooth’s enamel and the crown itself, creating what’s called a dentigerous cyst. When the space around an unerupted tooth exceeds 3 to 4 millimeters on an X-ray, a dentigerous cyst is suspected. At 5 millimeters or more, it’s considered diagnostic.
These cysts expand slowly and painlessly, sometimes over years. As they grow, they can hollow out the jawbone, displace neighboring teeth, and weaken the jaw structure. Third molars are the teeth most frequently involved. In rare cases, the tissue lining a cyst can transform into more aggressive pathology, including an odontogenic keratocyst or a tumor called an ameloblastoma. These are uncommon outcomes, but they’re the reason dentists monitor unerupted wisdom teeth with periodic X-rays rather than simply ignoring them.
Gum Disease and Chronic Inflammation
Even wisdom teeth that have fully erupted can cause problems if they’re difficult to reach with a toothbrush and floss. The area around third molars is one of the hardest spots in the mouth to keep clean, and chronic low-grade gum disease in that region is common in people who retain them. Research has found that semi-impacted or impacted third molars are associated with higher levels of systemic inflammation, including elevated markers like C-reactive protein and white blood cell counts. While this doesn’t mean a retained wisdom tooth will cause heart disease or diabetes, it does contribute to your body’s overall inflammatory burden.
The Crowding Myth
One of the most persistent reasons people consider wisdom tooth removal is the belief that erupting wisdom teeth will push the other teeth forward and cause crowding, especially in the lower front teeth. The scientific evidence doesn’t support this. A systematic review in Dentistry Journal found no proven connection between wisdom teeth and lower anterior crowding, including crowding that returns after orthodontic treatment. Multiple studies over several decades have reached the same conclusion: there isn’t adequate evidence to justify removing wisdom teeth for the purpose of preventing crowding.
Lower front teeth do tend to crowd slightly with age, but this happens in people with and without wisdom teeth. The forces involved in that shift appear to come from changes in the jaw and soft tissues over time, not from pressure exerted by third molars.
Does Waiting Make Removal Riskier?
A common concern is that if you skip removal in your late teens or early twenties and need it later, the surgery will be significantly more dangerous. The roots do become longer and more firmly anchored in bone as you age, and the bone itself becomes denser, which can make the procedure more involved. Delayed management has been linked to complications like slower healing and potential nerve damage during extraction.
However, a study comparing patients over 30 to those under 30 found no statistically significant difference in rates of nerve numbness, postoperative bleeding, or infection between the two groups. Age alone doesn’t appear to be the decisive risk factor that older guidance suggested. What matters more is the position of the tooth, how deeply it’s buried, and its proximity to the nerve that runs through the lower jaw.
What Monitoring Looks Like If You Keep Them
If your wisdom teeth are currently healthy and you choose to keep them, the recommended approach is active surveillance, not a “wait and see if something hurts” strategy. Specialists recommend follow-up visits roughly every 24 months that include both a clinical exam and X-rays. Your dentist or oral surgeon will check for changes in the tissue around the tooth, measure the depth of any gum pockets, and look at updated imaging for signs of cyst formation, bone loss, or root resorption of adjacent teeth.
The goal is to catch problems before they cause symptoms. Many of the complications described above, particularly cysts and root resorption, are painless in their early stages. By the time you feel something, the window for a simple fix may have closed. If you’re keeping your wisdom teeth, committing to that monitoring schedule is the single most important thing you can do to protect yourself.