Many expect a wisdom tooth to emerge at some point in their lives, and some get one or more — while others don’t. So, why do some people have wisdom teeth and others not? Generally, if you have a sizeable jaw or parents who have gotten one themselves, expect to get a wisdom tooth or two. Meanwhile, you might not get any if you have a small jaw or due to your genetics.
What are Wisdom Teeth?

Wisdom teeth are the last back teeth or molars that emerge at the furthest back part of your mouth.
They typically begin to emerge during the late teens or early adult years, usually between 17 and 25. However, the timing can vary, with some individuals experiencing them earlier or later in life.
But not everyone has wisdom teeth, and some may get one or two, but not all four. It’s also possible for them to not fully emerge in everyone who has them, and some may only become aware of their presence after getting a dental x-ray.
If you have wisdom teeth and are considering removal, it is generally advisable to do so at a younger age. The reason is the bones surrounding the gums are typically softer in youth, and the nerve roots in the mouth have yet to develop fully. These factors can make the extraction process considerably more manageable and less painful.
While scheduling wisdom teeth removal later in life is possible, waiting can pose more significant challenges. As individuals age, the bones become denser, and the nerve roots become more established, making the extraction procedure more complicated and potentially more uncomfortable.
What Factors Affect the Development of Wisdom Teeth?

Exposure to Medical Treatments
One fascinating insight into wisdom tooth development comes from medical treatments like chemotherapy, certain medications, and even local anesthesia injections in the gums.
For instance, studies have shown that children exposed to local anesthesia in the gums between the ages of 2 and 6 are less likely to develop wisdom teeth later. Medical interventions can play a role, although more research is necessary to draw definitive conclusions.
Ethnicity and Environmental Factors
It’s not just medicine that can impact whether or not you’ll have to deal with wisdom teeth. Ethnic background also plays a significant role. Different populations show varied patterns of wisdom tooth prevalence.
These differences could be a mix of genetic and environmental influences, like local dietary habits and lifestyles.
What Are the Potential Issues of Wisdom Teeth?

While not everyone will experience complications when developing wisdom teeth, understanding the risks can help you make informed decisions about removal.
Due to evolutionary changes, many people no longer have adequate space in their mouths to accommodate these late bloomers. This spatial limitation often leads to complications, ranging from mild discomfort to severe oral health issues.
Here are common complications linked to the third molars:
Tooth Pain
A throbbing pain on a tooth or two is often the first sign that your wisdom teeth are making their grand entrance. Initially, the discomfort might come and go, but if left unchecked, this can escalate into chronic pain that interferes with eating and speaking.
Swelling and Redness
Alongside pain, watch for swelling and redness in the gums around your third molars. Inflammation often indicates that your wisdom teeth struggle to emerge correctly, leading to discomfort and possible infection.
Impacted Wisdom Teeth
When wisdom teeth can’t erupt due to obstruction from other teeth or the jaw bone, they become impacted. This scenario can cause severe pain and may even lead to cyst formation.
Oral Infections
Wisdom teeth that are partially erupted create pockets where bacteria can accumulate. The result? Oral infections manifest through symptoms like pain, swelling, foul breath, or a disgusting taste in your mouth.
Cavities
Food particles can get trapped around partially emerged wisdom teeth, leading to cavities. Lack of adequate brushing space also puts adjacent teeth at risk.
Shifting Teeth
A lack of space can force other teeth to move, causing misalignment. This shifting can disrupt your bite and require orthodontic intervention.
If you’re dealing with any of these symptoms, it’s time to visit your dentist. A dental X-ray can provide a comprehensive view of your wisdom teeth, helping your dentist determine the best action.
If complications arise, your dentist will likely recommend removal by an oral surgeon. Remember that the bones in your jaw harden as you age, making the removal process more challenging and the recovery period longer.
Why Do Some People Have Wisdom Teeth? And Why Do We Need Them?

Wisdom teeth are like the appendix of the dental world — an evolutionary relic that doesn’t serve much purpose today. Our ancestors had a much rougher diet of raw plants and meat, leading to significant teeth wear and tear. The extra molars helped them chew better, making life a bit easier.
But as we evolved, our diets changed, and we moved from hunter-gatherer lifestyles to agricultural societies. Our jaws shrank, but our wisdom teeth didn’t get the memo. That’s why many people today face problems like impacted wisdom teeth and require extractions.
Do We Need Wisdom Teeth?
We don’t need wisdom teeth for survival or function today. Advances in food processing and dental care have made these molars redundant. They often do more harm than good, becoming impacted or misaligned, leading to dental issues, including pain, infection, and crowding of other teeth.
Geographical Prevalence of Wisdom Teeth: A Global Perspective
Interestingly, the absence of wisdom teeth varies significantly around the globe. While approximately 38.4% of the Bangladeshi population is missing at least one wisdom tooth, only 11.5% of people in India have the same characteristic. In Korea, the figure stands at a surprising 41%.
North American Trends
In the United States, the prevalence of missing wisdom teeth varies across ethnic groups. Estimates suggest that 10-25% of Americans with European ancestry lack at least one wisdom tooth, compared to 11% of African Americans and 40% of Asian Americans. The Inuit populations, indigenous to Arctic regions, display a unique trend — about 45% have at least one missing wisdom tooth.
Gender Differences in Wisdom Tooth Agenesis
A curious aspect of wisdom teeth is the gender difference. According to recent studies, women are more likely to miss at least one wisdom tooth than men.
Why Does It Matter?
Understanding the prevalence and issues associated with wisdom teeth can be vital for dental public health planning. It can also shed light on evolutionary biology, helping us know how we have evolved and continue to adapt.
Note: Statistics and prevalence rates are from available data as of 2022. Always consult a professional dental professional for medical advice and treatment.
Why Doesn’t Everyone Develop Wisdom Teeth?

Genetic research has opened new doors in understanding why some people never develop wisdom teeth. Specific genetic mutations that occurred thousands of years ago inhibit the formation of third molars. These genetic changes had nothing to do with brain development — they were all about the jaw and teeth.
Studies have found that the absence of wisdom teeth is heritable, meaning it runs in families. One study of identical and fraternal twins revealed that about 60-80% of the variation in third molar agenesis (absence of wisdom teeth) could be due to genetics. The rest is due to environmental factors.
Digging Into the Genes: AXIN2, MSX1, and PAX9
Many also link the absence of wisdom teeth to genes like AXIN2, MSX1, and PAX9. These genes play a role in facial and tooth development. While research on third molar agenesis is still in its infancy, some studies have suggested that polymorphisms in the PAX9 gene could be due to this phenomenon.
Aside from that, experts have implicated the gene THSD7B in some cases of third molar agenesis in Japanese and Korean populations.
Wisdom Teeth and Other Missing Teeth
Interestingly, individuals who are missing wisdom teeth often also lack other teeth. This correlation indicates that the same genetic factors that inhibit the growth of third molars might be at play for other teeth, pointing towards ongoing human evolution towards having fewer teeth.
Quick Note on Root Mineralization
Genetic factors are not just about the presence or absence of wisdom teeth — they also influence how fast the roots of these teeth mineralize. So, not only may you have fewer wisdom teeth than your ancestors, but the rate at which they develop could also be different!
So, whether you’re one of the lucky ones without wisdom teeth or you’ve had to go through the rite of passage that is wisdom tooth extraction, now you know that it’s all a fascinating blend of genetics and evolution.
The Future of Wisdom Teeth: A Toothless Tale?

Traditionally, wisdom teeth may have had a functional role in the lives of our ancestors, who needed strong molars to grind down plant tissue and raw meat. However, with advancements in dental care and changes in our diets, the utility of wisdom teeth has declined.
Some experts suggest that the genetic predisposition not to develop wisdom teeth, known as third molar agenesis, could become more common.
The idea that wisdom teeth could eventually become a thing of the past is intriguing. The availability of modern dental practices like braces, extractions, and advanced oral care has reduced the positive selection for third molar agenesis. However, as our lifestyles continue to evolve, so will our dental makeup, making wisdom teeth even less common than they are today.
Frequently Asked Questions
Q: What Are Wisdom Teeth, and Why Do Some People Have Them?
A: Wisdom teeth are the last set of molars at the back of the mouth, and some people have large enough jaws to accommodate them. These emerge in late adolescence or early adulthood, usually between 17 and 25. Many believe they’re evolutionary remnants of our ancestors who had more enormous jaws and needed them for grinding rigid plant material.
Q: Why Do Some People Not Have Wisdom Teeth?
A: You link the absence of wisdom teeth to genetic factors and evolution. This trait is inheritable, so if your parents didn’t have wisdom teeth, there’s a higher chance you won’t. Consequently, some people do not develop wisdom teeth because their jaws do not have enough space to accommodate them.
Q: What Problems Can Wisdom Teeth Cause?
A: Wisdom teeth issues can include impacted wisdom teeth, where the teeth become trapped beneath the gum line, causing pain, infection, or damage to adjacent teeth. Additionally, wisdom teeth can lead to crowding, misalignment, and dental issues, which may necessitate their removal through an extraction procedure.
Q: When Should I Have My Wisdom Tooth Removed?
A: The timing for wisdom teeth removal varies from person to person, depending on individual circumstances. However, removal may be ideal if there is evidence of impaction, pain, infection, or the potential for future dental problems. Generally, it is advisable to consider removal in the late teens or early twenties as your roots are still undergoing complete formation, making the extraction process less complicated.
Q: Is Wisdom Teeth Removal Always Necessary?
A: Wisdom teeth removal is not always necessary. After all, some individuals have enough space in their jaws to accommodate these teeth without causing problems. In such cases, they can keep their wisdom teeth while maintaining good oral hygiene and monitoring them regularly.
Wisdom Teeth Removal in Tijuana, Mexico
Why do some people have wisdom teeth? Due to genetics and a large jaw, some individuals still develop them during their late teens to early adulthood today, making grinding food more effortless. If you need to remove a wisdom tooth or two, you’re in the right place! Here at Dr. Mexico, we’ll help you if and when it has to go. Contact us for more information.