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Wisdom teeth or third molars: what are they and why do we have them?

20 October · 4 minutes

Our mouth undergoes several changes throughout our lives, one of which could be due to wisdom teeth coming through. In this article, we will look into why they are called wisdom teeth, what they are used for and when wisdom teeth have to be removed.

What are wisdom teeth?

You may be wondering what a wisdom tooth is. These molars, known as wisdom teeth although they are formally called third molars, are the final permanent teeth to emerge.

How long wisdom teeth take to grow varies in each person. In some cases, there is not enough space in the oral cavity which can, thus, cause misalignments and teeth crowding. Although they do not appear in everyone, there are four in total: two top wisdom teeth, in the upper jaw, and two bottom wisdom teeth, in the mandible.

Why are they called wisdom teeth?

They are called wisdom teeth because they usually emerge between the ages of 18 and 21. Whilst the rest of the teeth develop during childhood, wisdom teeth appear at an age in which people are considered to have a certain level of judgement and maturity.

Wisdom teeth are commonly referred to as such in different languages, so they are often translated in a similar way.

Why do we have wisdom teeth and what are they used for?

Wisdom teeth are used to help us chew food. Their purpose is similar to any other molar. They were very useful for our ancestors, as they helped them to chew hard, raw foods, like meat, or plants and roots that were difficult to break down.

Male dentist in lab coat holding up X-ray of mouth

When do wisdom teeth come in?

As previously mentioned, wisdom teeth do not come through for everyone. Although it varies from person to person, the age at which wisdom teeth usually come in is from 18 years old, approximately.

How long do wisdom teeth take to grow?

How long it takes for wisdom teeth to grow also varies for each person. For some, the four appear at once, whereas for others just one wisdom tooth does, or none at all. In the event of any discomfort, therefore, it is recommended that you see a specialist who will carry out the necessary tests to assess whether the wisdom teeth have enough room to come out and that they are doing so correctly, or whether it is necessary to remove them.

Wisdom teeth: symptoms and first signs

You may be wondering what the first signs of wisdom teeth coming in are. If there is not enough space in the oral cavity when a wisdom tooth starts to grow, you may notice symptoms such as red or swollen gums, bleeding, pain in the area or throughout the jaw and even headaches.

Whether or not you experience these signs of wisdom teeth emerging, we recommend that you regularly visit the dentist for a check-up, in order to maintain proper oral health and prevent future problems.

With an X-ray, the dentist will be able to see if there are any impacted wisdom teeth before symptoms occur.

Wisdom teeth removal

Wisdom teeth removal, which must be assessed by a dental specialist, is not recommended for all patients, as it is not necessary in some cases.

Let’s have a look at the situations in which wisdom teeth extraction is recommended.

When do wisdom teeth have to be removed?

If there is not enough space for the wisdom teeth to emerge correctly and they are causing pain or an infection in the patient, the dentist will recommend that the teeth in question are removed. The specialist will be responsible for assessing each case and deciding when to extract the wisdom teeth for prophylactic purposes, i.e. to prevent future problems or before orthodontic treatment.

Some of the reasons why wisdom teeth may have to be removed include:

  • Crowding with neighbouring teeth: if the third molars do not have enough space to develop properly, they can crowd adjacent teeth, damaging them.
  • Impacted wisdom teeth: these are completely hidden inside the gum. Hidden wisdom teeth can result in pain, caused by infections, which damage the roots or bones of adjacent teeth. In some cases, cysts or tumours can also form around them.
  • Partially erupted wisdom teeth: these half emerge from the gum and, due to the difficulty in maintaining proper oral hygiene in the area, food accumulates and causes the build-up of bacteria. This can then lead to cavities, abscesses in the gum and even infections.
  • Orthodontic prescription: when an orthodontic treatment requires it and an orthodontist has deemed it necessary, the wisdom teeth have to be removed.

Pros and cons of wisdom teeth removal

In many cases, wisdom teeth extraction is a necessary procedure. It can really impact a patient’s life for the better, especially when they have been dealing with unbearable pain due to infections caused by wisdom teeth. But this intervention can also have its side effects. Let’s see what the pros and cons of wisdom teeth removal are.

Female patient having an X-ray of her teeth

What are the benefits of removing wisdom teeth?

As previously mentioned, the benefits of removing wisdom teeth are mainly to avoid misalignments and teeth crowding, as well as prevent cavities and future problems in the patient.

Side effects of wisdom tooth extraction

Broadly speaking, there are no side effects of wisdom tooth extraction, although it is common for the patient to feel mild discomfort, such as pain in the area, swelling and bleeding, during the days following the procedure. The dentist may prescribe painkillers to alleviate the symptoms and will indicate how to clean and rinse the area during the first few hours post-treatment, or until the discomfort disappears.

What is the cost of wisdom teeth removal in the UK?

The cost of wisdom teeth removal depends on several factors, such as the type of procedure to be carried out, the number of wisdom teeth to be extracted and how they are positioned, as well as the clinic chosen, etc. In general, wisdom teeth removal in the UK can cost anything from ¬£62 upwards. 

Wisdom teeth removal and orthodontics

One of the most frequently asked questions by patients is if they need to undergo wisdom teeth removal before orthodontics. Each case must be assessed by a qualified orthodontist. Let’s have a look at the situations in which wisdom teeth extraction is recommended.

Do you need wisdom teeth removed for braces or to use aligners?

There are two types of malocclusions that require removal of the top and/or bottom wisdom teeth, along with distalization. In other words, depending on how the teeth are positioned, they will need to be shifted either backwards or forwards to move them into the desired position before using aligners or braces. This occurs when the patient has class II or III malocclusion.

In the following situations it would be necessary to remove the wisdom teeth before braces or orthodontics.

Let’s take a look at each of them:

  • Class II: in this malocclusion, the upper teeth are too far forward compared to the lower, so the teeth of the upper arch must be distalised and the top wisdom teeth removed. It could also result in an extraction of the bottom wisdom teeth as, without the upper teeth, they do not have a purpose of their own, although this depends on the case.
  • Class III: this is the contrary. The lower teeth are further forward than the upper, so the teeth of the lower arch will have to be distalised and, thus, the extraction of the bottom wisdom teeth is necessary. The top wisdom teeth may also need to be removed, for the same reason as the previous case.
Patient discussing X-ray with dentist and dental assistant

Can wisdom teeth move other teeth and ruin orthodontic work?

In the past, in order to prevent movement due to wisdom teeth emerging after orthodontics, dentists would recommend their removal. This is still a controversial issue today and, although it is not entirely clear, more and more studies show that wisdom teeth alone do not move other teeth and are, thus, not responsible for crowding or orthodontic relapse.

Nowadays, retainers (whether fixed or removable) are inserted at the end of orthodontic treatment. As long as these are used as indicated by the orthodontist, the alignment and final position of the teeth is maintained, ensuring that any growing wisdom teeth do not ruin orthodontic work. It is, therefore, essential that the patient follows the orthodontist's instructions and uses the retainers correctly, so that the results are maintained over time and relapses are avoided.

Wisdom teeth removal and Impress

If you are thinking about improving your smile and you want to know if your wisdom teeth have either emerged, or are going to, at Impress we can help. We will take X-rays and carry out the necessary tests to evaluate the condition of your third molars and make an assessment of your needs before starting orthodontic treatment.

Contact us and request an appointment without obligation to find out about our orthodontic treatments, prices and the pretreatments available at your nearest Impress clinic.

You can get in touch by booking an appointment through our website, by phone or WhatsApp on +44 20 3808 1072, or writing to us at

We look forward to meeting you!

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Frequently asked questions about wisdom teeth

Where are wisdom teeth located?

You may be wondering where wisdom teeth grow in the mouth. Although how long it takes for wisdom teeth to grow can vary, they are usually the last teeth to emerge: one is located on each side in the upper jaw and on each side in the lower jaw.

How many molars are there before the wisdom teeth?

As mentioned earlier, wisdom teeth are also known as third molars, indicating that there are two more molars on each side of either arch.

How many wisdom teeth do we have?

We have four wisdom teeth: two in the upper jaw and two in the mandible, although they may not all emerge and, for some, none grow at all.

How do you know if wisdom teeth are growing sideways?

To find out if your wisdom teeth are growing sideways, you should visit a specialist. The dentist will be able to carry out the necessary tests, such as an X-ray of the oral cavity, to determine if they are growing properly.

What to eat after wisdom teeth removal?

You are likely to feel some discomfort such as bleeding or swelling for the first few hours after the procedure. Until the effects of the anaesthesia wear off and the swelling goes down, it will be difficult to eat solid food after wisdom teeth removal, so we recommend you wait a few hours and start with soft food that is not too hot.


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