What Are Wisdom Teeth? All You Should Know About Wisdom Teeth

Wisdom teeth, also known as third molars, are the last teeth to erupt in the mouth. They are located at the very back of each quadrant of the mouth – upper left, upper right, lower left, and lower right. Typically you would have one wisdom tooth in each of these quadrants. 

The name "wisdom teeth" comes from the fact that they typically emerge much later than other teeth, usually between the ages of 17 and 25, a time traditionally associated with increased maturity or "wisdom." This late arrival sets them apart from the rest of your teeth.

Interestingly, not everyone develops wisdom teeth. Some people may have all four, some may have fewer, and some may not have any at all! It's estimated that around 20-30% of the population is missing at least one wisdom tooth¹. This absence, known as agenesis, can be influenced by genetics. Studies have shown that genes like PAX9 and MSX1 play a role in tooth development, and variations in these genes can contribute to the absence of wisdom teeth². These genetic variations can also differ across different populations, leading to variations in the prevalence of wisdom teeth agenesis.

Wisdom teeth look like other molars. They are typically large, flat teeth designed for grinding food. Most wisdom teeth have two or three roots, although the number and shape can vary. These roots can sometimes be fused together, curved, or splayed, which can complicate extraction if it becomes necessary. Understanding their structure helps in appreciating the challenges they can sometimes present.

From an evolutionary perspective, wisdom teeth were once more useful to our ancestors. Early humans consumed a diet of tougher, coarser foods that required more chewing power³. However, with the advent of modern diets, which are generally softer and more processed, the need for wisdom teeth has diminished. Our jaws have also become smaller over time, leaving less room for these late-arriving molars. This is why wisdom teeth often become impacted or cause other problems.

One of the most common issues associated with wisdom teeth is that it can be impacted. This happens when the wisdom tooth doesn't have enough space to erupt fully or develop normally. This can occur for several reasons, including a jaw that is simply too small to accommodate the wisdom tooth, other teeth or bone blocking the wisdom tooth's path, or the wisdom tooth growing at an angle that prevents it from erupting properly.

Impacted wisdom teeth can manifest in different forms; a partially impacted wisdom tooth has partially broken through the gum line, while a fully impacted wisdom tooth is completely trapped beneath the gum and bone. Angled impaction refers to a wisdom tooth growing at an angle, either towards other teeth, away from other teeth, or horizontally.

Even if wisdom teeth aren't fully impacted, they can still cause problems if they grow in misaligned positions. They might be positioned horizontally, growing sideways into the roots of adjacent teeth, or angled, leaning forward or backward, putting pressure on other teeth. Misalignment can lead to crowding, damage to neighbouring teeth, and difficulties with biting and chewing.

Wisdom teeth are often difficult to clean properly due to their location at the back of the mouth. This makes them more prone to decay and gum disease. The challenges in cleaning result in bacterial buildup, as food particles and bacteria can easily accumulate around wisdom teeth, leading to plaque and tartar formation. It can be hard to reach wisdom teeth with a toothbrush and floss. Partially erupted wisdom teeth can lead to pericoronitis, an inflammation of the gum tissue surrounding the tooth. This can cause pain, swelling, and infection.

Besides impaction, misalignment, decay, and gum disease, wisdom teeth can also cause other problems, including cyst formation. A cyst can form around an impacted wisdom tooth, potentially damaging adjacent teeth and bone. The pressure from erupting wisdom teeth can damage the roots of neighbouring molars. Pain, swelling, and infection are common symptoms associated with impacted or infected wisdom teeth.

Identifying potential wisdom tooth problems early is crucial for timely intervention. Here are some common signs and symptoms to watch out for: gum inflammation (redness or swelling in the gums behind the last molars), jaw pain, tenderness, or discomfort in the back of the mouth, pain radiating to the face due to pressure on nerves, white flecks or a partially erupted tooth visible behind the last molars, persistent bad breath (even after brushing, which can indicate an infection), and headaches (some people experience headaches due to the pressure from erupting wisdom teeth). If you experience any of these symptoms, it's important to consult with your dentist for a thorough examination.

The decision to remove wisdom teeth is a complex one that should be made in consultation with your dentist. There are several scenarios where extraction may be recommended.

Some dentists recommend preventative removal of wisdom teeth even before problems develop. The rationale behind this approach includes easier extraction at a younger age (the roots of wisdom teeth are less developed in younger individuals, making extraction easier and reducing the risk of complications) and prevention of future problems (removing wisdom teeth proactively can prevent impaction, misalignment, decay, and other issues that may arise later in life).

If wisdom teeth are already causing problems, extraction is often necessary. Common reasons for removal include persistent pain associated with wisdom teeth, recurring infections around the wisdom teeth, presence of cysts or tumors around the wisdom teeth, wisdom teeth causing damage to the roots of neighbouring molars, and wisdom teeth contributing to gum disease or bone loss.

Wisdom teeth removal may also be necessary during orthodontic treatment to create space for aligning other teeth properly and to prevent wisdom teeth from causing crowding after orthodontic treatment is complete.

Wisdom tooth removal is typically performed by an oral surgeon or dentist. The process usually involves numbing the area around the wisdom tooth with local anesthesia. The wisdom tooth is carefully extracted, sometimes requiring sectioning (cutting the tooth into smaller pieces) for easier removal. The gum is stitched back into place to promote healing.