As we age our mouths tend to grow and change. Whilst most people expect their permanent teeth to grow into their gums smoothly during their teenage years, the final set of molars (wisdom teeth) can often cause problems. When there is not enough room for them to grow into, these back teeth get stuck underneath the bone or gum. These are known as impacted wisdom teeth.

Understanding why wisdom teeth become impacted can help you understand why you may be suffering with pain, swelling or crowding in your back molars. Many people suffer with hidden pain, stiffness and sensitivity in their gums due to impacted back teeth. Understanding the main reasons for impacted wisdom teeth can help you understand why we suffer with this issue so commonly.

1. Evolution and Smaller Jaws

Evolution has played a huge part in impacted wisdom teeth. Our ancient human ancestors had much bigger and stronger jaws due to their diet and lifestyle. They would have eaten tough, raw roots, fibrous plants, wild meat and hard nuts every day. This caused our jawbones to grow strong and large to fit all 32 of our adult teeth.

Modern diets include lots of soft, processed and cooked food. Children are no longer eating tough foods which causes our jawbones to not grow as large or wide as they used to. Our jaws are now not long enough to fit the extra 4 large molars at the back of our mouths. Evolution has caused our wisdom teeth to become impacted as there is nowhere for them to go. Generations of humans mixing together has also made our jaws even smaller.

  • Ancient diets caused jawbones to become large due to tough chewing.

  • Modern diets cause less jaw stimulation and growth.

  • Smaller modern jaw sizes cause extreme crowding.

  • Evolution has caused us to have too many teeth.

  • Mixing of genes has resulted in smaller jaw sizes.

2. Genetics

Many parts of our bodies are determined by our genes. This includes our facial structure, bone size and teeth size. If your parents or grandparents suffered with impacted wisdom teeth, you are likely to suffer with the same issue.

Our genes determine how large our upper and lower jaw will grow. They also determine how large our permanent teeth will be. Sometimes you can get a large set of teeth from one parent and a small jawbone from another. This will cause extreme crowding. As your back molars are the last to come through there will be no room in your jaw. This causes your wisdom teeth to become impacted as there is no extra room. The shape of your face bone has also been determined by genetics.

  • Jaw and tooth size determined by genetics.

  • Family history can cause crowding.

  • Permanent teeth come through at a specific time determined by genetics.

  • Parents with opposite features cause tight spaces for wisdom teeth.

  • Angle of bone determined by genetics.

3. Late Eruption

Most permanent teeth will come through between the ages of 6-12. Wisdom teeth however will usually come through much later, often when you are in late adolescence or early adulthood (aged 17-25).

By the time your wisdom teeth try to come through you will already have 28 fully formed adult teeth. This means there will be no room in your mouth whatsoever. Your wisdom teeth are coming through way too late. As your second molars are already in place there will be no room for your wisdom teeth to come through. This causes them to hit solid bone or neighboring roots. This causes complete blockage.

  • Wisdom teeth come through much later than any other permanent teeth.

  • 28 adult teeth will already be in your mouth.

  • No room for third molars.

  • Wisdom teeth hit neighboring second molars.

  • Extreme crowding causes intense pressure.

4. Abnormal Angles

Teeth should grow straight up. Unfortunately wisdom teeth often grow at odd angles inside your jawbone.

Abnormal angles cause wisdom teeth to not erupt. Sometimes they may grow forwards causing them to hit your second molars. Other times they may grow backwards or horizontally. This causes them to be stuck inside your jawbone. The root of the teeth often become stuck in this position.

  • Abnormal angles cause teeth not to grow upwards.

  • Forward angles cause wisdom teeth to hit neighboring second molars.

  • Horizontal angles cause teeth to be stuck inside jaw.

  • Odd angles cause roots to become stuck inside dense bone.

  • Roots become stuck causing misalignment.

5. Premature Baby Teeth Loss

The order baby teeth fall out can affect the position your permanent teeth will grow in. Losing baby teeth prematurely can cause unexpected issues.

If your child loses their baby molars prematurely due to severe decay or trauma neighboring teeth will move. This causes them to move without permission and take up valuable space. When your wisdom teeth try to come through years later there will be no room for them to come through. The teeth will hit the moved teeth and compressed bone. Premature crowding can cause a chain reaction which causes your wisdom teeth to become impacted in early adulthood. Often lack of orthodontics in childhood can make this worse.

  • Premature loss of baby teeth causes neighboring teeth to move.

  • Neighboring teeth take up valuable space.

  • Compression causes wisdom teeth not to come through.

  • Premature crowding causes severe crowding in adult mouths.

  • Lack of orthodontics makes crowding worse.

6. Soft Diet

The food your child eats can affect how strong their jawbones develop. Modern children eat lots of soft processed foods.

Chewing causes force on jawbones causing cells to multiply. Soft diets mean your jawbones will not get enough exercise. This means they will be smaller, thinner and not as developed. This means they won’t have enough room for the extra 4 molars. This causes your wisdom teeth to become impacted. Parents can encourage harder foods but modern food is often very soft.

  • Soft diets in childhood cause less jaw exercise.

  • No chewing causes less bone growth.

  • Underdeveloped jawbones won’t have room for extra molars.

  • Poor development causes wisdom teeth to become impacted.

  • Processed foods mean no natural resistance.

7. Tumors and Cysts

Sometimes there can be rare abnormalities in your jawbone which cause your wisdom teeth not to erupt.

Sometimes fluid filled cysts can grow around the crown of an impacted wisdom tooth. As they grow they will push your teeth out of place and destroy bone. Benign tumors or thick scar tissue from previous injuries can also cause blockage. These rare issues need to be diagnosed quickly by a professional and surgically removed by a trained oral surgeon. If left they will cause damage to surrounding facial structures.

  • Cysts form around impacted wisdom tooth crowns.

  • Cysts grow causing teeth to become misaligned and destroying bone.

  • Benign tumors cause blockage.

  • Scar tissue from previous injuries cause wisdom teeth to become impacted.

  • Physical blockage causes widespread damage if left.

Common Symptoms of Impacted Wisdom Teeth

Impacted wisdom teeth can cause uncomfortable symptoms. Knowing the signs can help to avoid severe infections. Signs to look out for include:

  • Constant dull ache or pressure at the back of your jaw.

  • Swollen, sensitive, red or bleeding gums around your back molars.

  • Stiff jaw, difficulty opening your mouth fully or painful chewing.

  • Chronic bad breath or bad taste due to trapped bacteria.

  • Pressure headaches or pain radiating towards your temples.

Prevention and Diagnosis

Unfortunately you can’t prevent genetic issues or evolution but you can keep an eye on your teeth development. Dentists will take panoramic x-rays in adolescence to see how your wisdom teeth are growing.

This allows your dentist to know if your wisdom teeth will come through or become impacted. If they show extreme angles or no room at all your dentist will recommend having them removed proactively. This will help to avoid painful symptoms, root damage or cysts. Having them removed early will prevent future infections and protect your neighboring teeth. Modern technology means procedures will be safe and comfortable for young adults.

  • Regular check ups will help to keep track of your wisdom teeth growth in teen years.

  • Panoramic x-rays will show hidden angles and crowding.

  • Proactive removal will help to avoid severe infections, pain and neighboring root damage.

  • Early removal will protect your long term dental alignment.

  • Modern procedures will ensure you are comfortable.

FAQs

1. Do I need my impacted wisdom teeth removed?

Not always. If your impacted wisdom teeth are fully impacted, not causing any pain and not causing any issues to neighboring teeth your dentist may just keep an eye on them. If they are infected, causing pain or decay they will need to be removed.

2. What age do wisdom teeth usually become impacted?

Wisdom teeth usually try to erupt between the ages of 17-25.

3. Can impacted wisdom teeth cause damage to neighboring teeth?

Yes. When impacted wisdom teeth push against neighboring second molars it causes intense pressure. This causes root damage to neighboring teeth and causes deep decay pockets.

4. How do dentists diagnose impacted wisdom teeth?

Dentists will carry out a physical examination, ask about symptoms and use advanced technology to see the exact position of impacted wisdom teeth. This could include panoramic x-rays or 3D CBCT scans.

Understanding why impacted wisdom teeth occur can help you take control of your oral health. There are many reasons why they can become impacted including smaller modern jaw sizes, soft childhood diets, late eruption and abnormal angles. Book a professional appointment to check your wisdom teeth alignment.