The third adult molar teeth are commonly called ‘wisdom teeth’. These are usually the last teeth to appear in the mouth, generally around the age of 18 - 25 years.

Most people will have four wisdom teeth, but they may never or only partially appear in the mouth. Some people will not develop wisdom teeth.

Wisdom teeth are often impacted, meaning something is stopping them from pushing all the way into the mouth. This may be a lack of space between the second molar tooth and the bone behind.

Your dentist will examine your mouth. If they cannot see your wisdom teeth inside your mouth because they are still under the gums, your dentist may ask to take a radiograph (x-ray).

The x-ray is known as an orthopantomogram (OPG) and displays all your teeth (erupted and unerupted) on one image.

This helps your dentist to see the position of the teeth, the shape of their roots and if the wisdom teeth are close to important anatomical structures, such as nerves.

If you are going to have your wisdom teeth removed, the x-ray helps your dentist to plan this treatment.

When wisdom teeth push into the mouth, they can cause feelings of pressure.

Sometimes people worry that the wisdom teeth may cause their other teeth to become crooked. There is currently no evidence that supports this theory.

When wisdom teeth are pushing through the gums and into the mouth, it is important to keep the area clean.

Not cleaning the bacteria away can cause the gums around the wisdom teeth that are only partially present in the mouth to become inflamed.

Ensure your toothbrush reaches all the way back to the wisdom teeth. Sometimes the space in this area is limited. Using a toothbrush with a small brush head can help. Keeping your mouth almost closed while brushing can give you more space to reach around the cheek sides of the wisdom teeth when brushing.

If you are finding it difficult to brush or there is pain from severely inflamed gums, using an antibacterial mouthwash can help you to care for the wisdom teeth and surrounding gums. But this should not be a long-term replacement for brushing.

Wisdom teeth may be unable to move from under the gums and into the mouth as the rest of the teeth do.

Many people do not have enough space in their jaws for wisdom teeth to easily push through the gums. If there is not enough space, the wisdom tooth will become impacted.

This means they either remain under the gum or may have been able to only partially break through the gum and a small portion of the tooth can be seen in the mouth.

A wisdom tooth may be sitting at an angle that is causing it to bump into the tooth in front which stops it from moving into the mouth.

Problems caused by impacted wisdom teeth can include infection, pain, cysts, ulcers, food can become stuck and tooth decay can develop on the wisdom tooth or the tooth in front that the wisdom tooth is butting into.

If your impacted wisdom teeth are causing no problems the risks of removing them may outweigh the benefits.

If impacted wisdom teeth are causing problems, they may need removal. Your dentist is the best person to discuss with you the specifics of your wisdom teeth and what your options are in their management.

There are several reasons why wisdom teeth may need to be removed.

• The teeth are impacted.
• They and/or the tooth in front of it are at risk of developing tooth decay or gum disease.
• The gum around the wisdom tooth becomes infected multiple times.
• They may be affected by a cyst or tumour.

Wisdom teeth can be removed by your general dentist or a dental specialist, such as an oral surgeon or a maxillofacial surgeon. The teeth can be removed in the dental chair or within a hospital.

Wisdom teeth may be removed under local anaesthesia. The anaesthetic is provided in a similar way to when a dentist makes a tooth numb for a filling.

Other types of anaesthetic include local anaesthetic in combination with conscious sedation, or general anaesthesia. Conscious sedation is a combination of medicines to help you relax and to block pain during a medical or dental procedure, such as nitrous oxide, commonly known as 'happy gas'. These anaesthetics can be performed in hospitals and some dental clinics.

Risks & complications

The risks and complications of removing wisdom teeth will be explained prior to any treatment as part of obtaining informed consent. Possible complications following wisdom tooth removal can include:

• Damage to the nerves that travel to and supply feeling to the wisdom teeth and nearby parts of the face. This can cause feelings of numbness or 'pins and needles' in the parts of the face and mouth that these nerves give feeling to – this may be temporary or permanent.
• A dry socket (painful inflammation of the extraction socket).
• Swelling and/or infection.
• Damage to nearby teeth.
• Difficulty opening the mouth, often associated with swelling.
• Excessive bleeding.
• Pain.
• An opening from the mouth to the maxillary sinus (related to upper wisdom teeth removal only).