Nothing might happen, or quite a lot might. Many people keep their wisdom teeth for life without any problems, but a significant percentage eventually develop complications like infection, decay, gum disease, or damage to neighboring teeth. The outcome depends almost entirely on how your specific wisdom teeth are positioned and whether they have enough room to fully emerge.
The key distinction is between wisdom teeth that are fully erupted, easy to clean, and functioning normally versus those that are impacted (stuck in the jawbone), partially erupted, or angled into the tooth next door. The first group can often stay. The second group carries real, cumulative risks that tend to increase with time.
Pericoronitis: The Most Common Problem
When a wisdom tooth only partially breaks through the gum, a flap of tissue called an operculum forms over part of the tooth’s crown. Food, bacteria, and debris get trapped underneath this flap in a pocket that’s nearly impossible to clean with a toothbrush or floss. The result is pericoronitis, an infection of the gum tissue surrounding the partially erupted tooth.
Chronic pericoronitis can simmer for months or years as a mild ache near the back of your mouth, bad breath, and an unpleasant taste. Acute episodes are more dramatic: severe pain, swollen and red gums, pus, difficulty swallowing, and sometimes fever. In advanced cases, the infection can spread into the deeper tissue spaces of the head and neck, causing facial swelling, lockjaw, and even airway compromise. The upper wisdom teeth can make things worse by biting down repeatedly on the inflamed gum tissue over a lower wisdom tooth, creating ulcers and intensifying the cycle.
Pericoronitis tends to recur. Treating it with antibiotics or irrigation manages the episode but doesn’t fix the underlying anatomy. If the tooth can’t fully erupt, the pocket stays, and the infection usually comes back.
Decay in the Wisdom Tooth and Its Neighbor
A partially erupted or angled wisdom tooth creates a tight, hard-to-reach space between itself and the second molar directly in front of it. Normal brushing and flossing can’t reach this gap effectively, so bacteria and food accumulate there. Over time, cavities develop on one or both teeth.
Cavities on the wisdom tooth itself are often impractical to fill because of limited access, and they can progress to the point where the tooth’s nerve dies and an abscess forms. But the more consequential damage is often to the second molar, a tooth you actually need. If decay on the second molar goes undetected for too long, restoring it may require a crown, a root canal, or extraction of the second molar as well.
Damage to the Roots of Adjacent Teeth
When an impacted wisdom tooth is angled toward the second molar, it can press against the root of that neighboring tooth and gradually dissolve it, a process called external root resorption. One imaging study using 3D scans found that nearly 48% of second molars adjacent to impacted lower wisdom teeth showed some degree of root resorption. Not all of this resorption is severe enough to threaten the tooth, but significant cases can weaken the second molar or even make it unsalvageable.
This kind of damage is painless and invisible without an X-ray, which is one reason dentists recommend periodic imaging of retained wisdom teeth even when you feel fine.
Gum Disease in the Back of the Mouth
Retained wisdom teeth, particularly visible or partially erupted ones, are associated with deeper periodontal pockets on the second molar. Research has found that having a visible wisdom tooth is linked to about 1.5 times the odds of increased pocket depth on the adjacent second molar. Roughly 25% of patients with retained, symptom-free wisdom teeth showed notable periodontal problems in the back of the mouth in one study.
Periodontal pockets harbor bacteria that break down the bone and connective tissue supporting your teeth. This bone loss is largely irreversible. The tricky part is that gum disease in this area often progresses silently, without obvious pain, until the supporting bone is significantly compromised.
Cysts and Tumors
Every unerupted tooth sits inside a small sac of tissue called a follicle. In rare cases, fluid accumulates in this follicle and forms a dentigerous cyst, a fluid-filled sac that slowly expands within the jawbone. The reported incidence is roughly 1 to 6 per 100 unerupted teeth, with the lower wisdom teeth and upper canines being the most commonly affected.
These cysts grow gradually and can displace neighboring teeth, compress nerves (causing numbness or tingling), and weaken the jawbone. In uncommon cases, the lining of the cyst can undergo changes that lead to more serious growths, including certain types of jaw tumors. This is rare, but it’s the reason dentists recommend routine X-rays every couple of years if you’re keeping impacted wisdom teeth.
Not Everyone Needs Them Removed
Current clinical guidelines do not recommend removing wisdom teeth that are fully impacted, symptom-free, and show no signs of disease on imaging. In those cases, the evidence actually favors leaving them alone, because the surgery itself carries risks of temporary or occasionally lasting complications like nerve numbness, dry socket, infection, and jaw stiffness. For people over 25, the complication rate from extraction is higher. One large study of nearly 9,000 wisdom tooth removals found that being older than 25 increased the risk of surgical complications by about 50% compared to younger patients.
The trade-off is straightforward: avoiding surgery now means committing to ongoing monitoring. Guidelines recommend clinical check-ups every six to twelve months and panoramic X-rays roughly every two years for retained wisdom teeth. This surveillance catches developing problems early, before they damage adjacent teeth or bone.
The Crowding Question
Many people believe wisdom teeth push the other teeth forward and cause crowding, especially in the lower front teeth. The scientific evidence on this is genuinely mixed. Some studies support a small effect, but others find no meaningful connection. Lower front teeth tend to shift and crowd naturally with age due to a combination of factors including jaw growth patterns, tooth size, and changes in the supporting bone, regardless of whether wisdom teeth are present. Preventing crowding alone is not considered a strong reason for extraction.
What Matters for Your Decision
The practical question is whether your specific wisdom teeth are positioned in a way that creates ongoing risk. A fully erupted, upright wisdom tooth that you can brush and floss normally is not inherently a problem. A partially erupted tooth tilted at 45 degrees into your second molar is a different situation entirely, even if it doesn’t hurt right now.
Your dentist’s recommendation should be based on your X-rays, the position and angulation of each tooth, whether there’s already evidence of decay, bone loss, or cyst formation, and your age. If you’re in your late teens or early twenties and extraction is recommended for a problematic tooth, the surgery is generally simpler and recovery faster than if you wait until your 30s or 40s, when the roots are fully formed and the surrounding bone is denser. If you choose to keep them, the commitment to regular monitoring is not optional. Problems with retained wisdom teeth tend to develop slowly and silently, and catching them early is the difference between a simple extraction and losing a second molar along with it.