What Age Do Your Wisdom Teeth Start Growing?

Wisdom teeth begin forming deep inside the jawbone surprisingly early, with the first signs of development appearing around ages six or seven. Most people associate wisdom teeth with the late teens and early twenties, but that is when they push through the gums. The actual growth process starts more than a decade before eruption and unfolds in stages that vary by individual, sex, and genetic background.

The Hidden First Stage

Long before you feel anything, your wisdom teeth start as tiny pockets called crypts in the jawbone. A radiographic study of patients aged six to twenty-four found that crypt formation in the lower jaw was visible as early as age six, and in the upper jaw by age seven.¹ These crypts are the biological blueprint for each tooth, the spaces where mineralization will eventually begin. At this point there is no hard tooth structure yet, just the soft tissue outline of what will become a wisdom tooth.

Initial mineralization, when the crown actually starts calcifying, typically picks up a few years later and can span a wide window from roughly age seven through the early teens. That same study noted the earliest mineralization stage was seen from age seven and rarely observed beyond fourteen. Crown calcification then progresses steadily: research on a Turkish population found that complete crown formation was reached around age fifteen for both upper and lower wisdom teeth in both sexes.² After the crown finishes, root development continues for several more years, which is why wisdom teeth are still “growing” well into someone’s twenties even if the crown formed years ago.

When They Actually Break Through the Gums

Eruption is the part people notice and talk about, and it happens much later than the underground development. The earliest anyone’s wisdom teeth poke through the bone (called alveolar emergence) varies across studies and populations, but the youngest ages reported tend to fall in the mid-teens. A study of a German population found that alveolar emergence occurred as early as twelve in some females and around fifteen in males.³ A Japanese study placed the minimum age of alveolar emergence between about fifteen and eighteen depending on jaw location and sex.⁴

Those are minimums, though. The average ages are considerably higher. An Indian study found mean alveolar emergence ranging from about seventeen to nineteen in women and nineteen to nearly twenty-two in men. Full gingival emergence, where the tooth is actually visible in the mouth and functional, came even later: the most probable age was roughly eighteen to twenty-two in women and twenty-two to twenty-five in men.⁵ So while a few people see their wisdom teeth arrive in high school, most are well into college age or beyond before they fully come in.

Why the Timing Varies So Much Between People

One of the more counterintuitive findings in dental research is that sex differences in wisdom tooth development are not straightforward. Females tend to be ahead of males in the early stages of mineralization by roughly half a year to a year. But that lead reverses later in development. A large German study found that males completed root development about a year earlier than females on average, contradicting the general expectation that female dental development simply outpaces males across the board.⁶ A separate analysis confirmed this pattern, showing male individuals were roughly a year ahead of females at the final root stage, with Southeast Europeans also about six months ahead of Central Europeans at the same stage.⁷

The mention of population differences there is not incidental. Genetics plays a large role in whether your wisdom teeth form at all, how quickly they develop, and how many you end up with. A twin study found that formation of third molars is strongly controlled by genetic factors, with additive genetics accounting for about 62 to 63 percent of maxillary (upper) third molar agenesis and 81 to 83 percent of mandibular (lower) third molar agenesis.⁸ A genome-wide study in Japanese and Korean populations identified specific genetic variants associated with being born without one or more wisdom teeth, with the strongest signal mapping to a gene on chromosome 2.⁹ In other words, the reason your friend had wisdom teeth at sixteen and you still haven’t seen yours at twenty-three is probably written into your DNA more than anything else.

Hormonal and nutritional factors also play a part. Children with growth hormone deficiency show delayed eruption of permanent teeth compared to peers, and while this research focused on earlier teeth like incisors and first molars, it illustrates that systemic health shapes the dental timeline broadly.¹⁰

Why So Many Wisdom Teeth Get Stuck

The most common outcome for wisdom teeth in modern humans is that they do not fully erupt. About 72 percent of Swedish people aged twenty to thirty have at least one impacted wisdom tooth, meaning a tooth that has failed to emerge into its proper position because of lack of space, obstruction, or abnormal angulation.¹¹ That is not a quirk of Scandinavian jaws; similar rates are reported across industrialized populations.

The leading explanation ties impaction to jaw size. Our jaws have gotten smaller over evolutionary time, and the shift accelerated with the agricultural and industrial revolutions. Softer, more processed diets require less chewing force during childhood, which means less mechanical stimulation for jaw growth. Researchers have debated how much of this is about chewing force versus habitual oral posture, with some evidence suggesting that reduced postural demands on the jaw during growth may matter as much as or more than reduced chewing itself.¹² Either way, the result is the same: the back of the jaw often does not have enough room for those last four teeth, so they come in crooked, stay buried, or only partially emerge.

A pilot study on children found that the type and timing of solid food introduction was associated with measurable differences in jaw development, including the spacing between teeth and the alignment of back teeth.¹³ This is still early-stage research, but it reinforces the idea that what you eat during childhood shapes the space available for wisdom teeth a decade or more later.

Problems That Can Come with Eruption

Partially erupted wisdom teeth are especially prone to trouble. The flap of gum tissue that partially covers them creates a pocket where bacteria thrive, leading to pericoronitis, an infection of the tissue around the crown. A study of mandibular third molar impactions found pericoronitis was the most common symptom across all patients. The pattern of impaction mattered, too: vertically impacted and soft-tissue-impacted teeth were most associated with pericoronitis, while teeth angled toward the neighboring molar at shallower depths carried a greater risk of causing cavities in that neighbor.¹⁴

The damage wisdom teeth can cause to adjacent second molars is sometimes underappreciated. Impacted wisdom teeth that lean forward create a contact point with the second molar where food packs in and bacteria accumulate. This can lead to cavities on the back surface of the second molar, gum disease around it, and in rarer cases resorption of the second molar’s root.¹⁵ These effects are not limited to young adults. A study of elderly patients found that erupted third molars continued to be a risk factor for both periodontal disease and cavities in adjacent second molars well into later life.¹⁶

The Debate Over Removing Healthy Wisdom Teeth

If your wisdom teeth come in without symptoms and show no signs of disease, should you still have them removed? This question has been argued over for decades, and the evidence remains surprisingly thin. The most recent Cochrane review on the topic concluded there is insufficient evidence to determine whether asymptomatic, disease-free impacted wisdom teeth should be removed or kept. The reviewers noted that retention may carry an increased long-term risk of gum disease around the second molar, but rated the evidence for this as very low certainty.¹⁷

Their practical recommendation boiled down to shared decision-making between patient and clinician. If you decide to keep asymptomatic wisdom teeth, regular check-ups are important because about a third of unerupted wisdom teeth will shift position over time, potentially becoming partially erupted in a way that creates new problems.¹¹ The absence of symptoms today does not guarantee absence of symptoms five years from now.

What Extraction Actually Risks

Extraction of lower wisdom teeth comes with a specific nerve-related risk that is worth understanding before surgery. The inferior alveolar nerve runs through the lower jaw very close to the roots of the wisdom teeth, and damage to this nerve can cause numbness or altered sensation in the lower lip, chin, or gums on that side. A literature review found the overall incidence of nerve-related sensory disturbance was about 2.5 percent per tooth removal. The risk depended heavily on how close the roots sat to the nerve: when the tooth was classified as “intimate” with the nerve canal, the rate jumped to 11 percent. Permanent sensory loss, however, was rare at under one percent.¹⁸

This is one reason dentists often use cone-beam CT imaging before removing lower wisdom teeth in complex cases. The anatomy of the nerve’s path varies from person to person, and knowing its exact position relative to the roots changes the surgical approach.¹⁹ Upper wisdom teeth carry their own risks, including potential communication with the sinus cavity, but nerve injury is less of a concern on that side because the relevant nerves are farther from the surgical site.

How Braces Affect Wisdom Tooth Eruption

Parents often worry that orthodontic treatment will crowd the back of the mouth and make wisdom tooth impaction worse. The picture from research is more nuanced than that. One longitudinal study found that orthodontic treatment without premolar extractions was associated with significantly more eruption problems for wisdom teeth, and those wisdom teeth sat closer to the nerve in the lower jaw.²⁰ In other words, when premolars were removed as part of orthodontic treatment, the resulting space allowed wisdom teeth a better chance of erupting normally.

A separate study compared treated and untreated groups directly. Impaction rates were similar between the two (about 73 percent impacted in the treated group versus 79 percent in the untreated group, a difference that was not statistically significant). But the treated group had a significantly higher predicted rate of partial eruption and a significantly lower rate of impossible eruption compared to untreated patients.²¹ So orthodontic work does not cause or prevent impaction in any dramatic way, but the specifics of the treatment plan, particularly whether premolars are extracted, can shift the odds of successful eruption.

Wisdom Teeth as a Forensic Clock

Because wisdom teeth develop on a relatively predictable schedule, they are one of the tools used in forensic age estimation, particularly for adolescents and young adults whose age is unknown or disputed. The basic idea is straightforward: the degree of mineralization visible on a panoramic X-ray can be matched to known age ranges. Lower wisdom teeth tend to give slightly better age predictions than upper ones.²²

Combining wisdom tooth mineralization with other indicators, like clavicle ossification, improves accuracy further. One study found that adding a single wisdom tooth’s mineralization data to clavicle data improved predictive accuracy by about 14 to 15 percent.²³ A large retrospective study in a Belgian population found that when all four wisdom teeth were present and development was complete, there was roughly a 95 to 96 percent chance the individual was over eighteen.²⁴ This has real-world consequences in immigration cases and criminal proceedings where a person’s age determines legal outcomes. The limitation, of course, is that wisdom tooth development varies enough between individuals and populations that it provides a probability, not a definitive answer.