Coronectomy

About a coronectomy

A coronectomy is the removal of the crown (top) of a tooth, while leaving the roots behind.

We leave the roots to avoid damaging your IAN (Inferior Alveolar Nerve), which is the nerve that supplies feeling to your lip and chin.

Through a natural bodily process, the roots which remain in place are eventually sealed over with bone. Roots covered by bone can remain buried in the jaw for years. They rarely cause problems.

Why we recommend a coronectomy

We usually recommend this procedure if your tooth lies very close to your IAN nerve, and a normal type of extraction carries a high risk of nerve damage.

We will confirm that you need a coronectomy by taking a CBCT scan. This is a type of 3D X-ray which we use to create 3D images.

During the procedure

During the procedure, your surgeon will do the following:

• inject anaesthetic into your gum, to make the area numb
• make an incision (cut) in your gum to uncover the tooth
• drill away a small amount of your jaw bone
• remove the top part of your tooth, and leave the roots in place
• smooth down the roots, below the level of your jaw bone
• use dissolving stitches to close the wound, so that it covers the root.

Risks and side effects

Removal of whole tooth

When we remove the crown, the roots can become mobile (especially if they are cone-shaped). If the roots become mobile, we will need to remove them. This risks damage to your IAN (the nerve that supplies feeling to your lip and chin).

Incomplete removal of crown

If the position of your wisdom tooth makes it hard for us to see and remove the whole of your crown, we may leave behind some enamel.

If this happens, it can irritate the overlying gum and increase the chances of the tooth socket becoming infected.

Root migration

It is common for the tooth roots to move away from the IAN. This usually happens during the first 6 months after the coronectomy. This root movement stops as your bone naturally heals over the roots.

Numbness

There may be damage to the nerves that control sensation for your lower jaw, tongue and teeth. This can cause numbness or altered sensation (such as a tingling or burning feeling) in your tongue and/or chin and lower lip. This side effect does not last long and is rare.

Infection

There is a risk of infection in the root that we leave behind. If it becomes infected, you will need a course of antibiotics. Some patients may need another procedure, to remove the remaining tooth root.

Recovery at home

Follow this guidance while you recover after your procedure.

Pain

You can expect to experience some soreness afterwards. This can last up to 10 days. We advise you to use over-the-counter painkillers, such as ibuprofen or paracetamol.

Swelling

You can expect some facial swelling afterwards. This can last up to 7 days. We advise you to avoid alcohol, smoking and exercising in the 48 hours after the procedure. This will help to decrease the swelling.

Bruising

This procedure can result in significant bruising. Older patients, and those on regular aspirin or steroids, will bruise more easily. It can take 14 days for the bruising to go away.

Limited mouth opening (trismus)

The chewing muscles and jaw joints can be sore after this procedure. You may find that your mouth does not open fully for up to 7 days.

Stitches

The dissolvable stitches we use will fall out within 10 to 14 days.