Numbness After Wisdom Tooth Removal: Nerve Risk, Planning and Recovery

Which nerves are close to your wisdom teeth?

Two nerves matter for lower wisdom teeth:

• The inferior alveolar nerve runs through a canal inside the lower jaw, beneath the roots of the back teeth. It gives feeling to the lower teeth, the lower lip and the skin of the chin on that side. The roots of a lower wisdom tooth sometimes sit right next to this canal, curve around it or even appear to cross it.
• The lingual nerve runs along the inner (tongue) side of the jaw, close to the gum next to the lower wisdom tooth. It gives feeling to the side of the tongue and carries taste from the front of the tongue.

Upper wisdom teeth do not have a comparable nerve beside them. Their main nearby structure is the maxillary sinus, which is a different consideration.

Nerve injury is not the same as the normal numbness of local anaesthetic, which wears off within hours. It means a change in feeling that is still present the day after surgery or later. The NHS describes damage to nerves near the tooth, causing numbness or tingling in the tongue, lips and chin, as a possible complication that usually gets better but can last a few weeks or months.

Normal numbness or a nerve problem?

How does CBCT planning reduce nerve risk?

Planning starts with a panoramic X-ray. Certain features on it suggest that a lower wisdom tooth's roots and the nerve canal are in close contact: the roots appearing darker where the canal crosses them, the white outline of the canal being interrupted, or the canal changing direction or narrowing at the roots.

When those signs are present, a 3D CBCT scan shows the actual relationship: whether the canal runs below, beside or between the roots, how thin the bone between them is, and where the lingual plate of bone is. The surgeon can then plan the approach, for example dividing the tooth so the roots can be lifted away from the nerve rather than levered against it, and decide where to place instruments. The scan also allows the risk to be explained to you in terms of your own tooth, rather than in general numbers.

No scan removes the risk entirely. What planning does is reduce avoidable risk, identify the teeth where it is higher, and make sure you can weigh it before agreeing to surgery. If the tooth is causing no problems and the nerve is very close, the honest answer may be to leave it and monitor it; our guide do wisdom teeth need removing? explains when that is reasonable.

What makes nerve injury more likely?

• Roots in close contact with the nerve canal on the X-ray or CBCT scan, which is the most important factor.
• Deeply impacted or horizontally lying teeth, which need more bone removal.
• Older age, when the roots are fully formed and the bone is denser; this is one reason a wisdom tooth that clearly needs to come out is often removed earlier rather than later.
• A tooth positioned towards the tongue side, close to the lingual nerve.
• A difficult surgical approach, which is why complex lower wisdom teeth are often referred to an oral and maxillofacial surgeon.

Many straightforward wisdom teeth are removed by general dentists. Teeth with roots close to the nerve, deep impactions and cases needing sedation are commonly handled by a surgeon. At Creative Arts, Dr. Firas Osman, Oral & Maxillofacial Surgeon & Implantologist, assesses and removes complex wisdom teeth, while Dr. Khalid Saeed and Dr. Somar Dahdal carry out routine extractions.

What is a coronectomy, and when is it considered?

A coronectomy removes the crown of a lower wisdom tooth, the part that causes problems such as gum infection and decay, while deliberately leaving the roots in place where they are in close contact with the nerve. The roots are left below the bone level so the gum can heal over them.

It may be considered in some cases where the CBCT scan shows the roots wrapped around or pressed against the nerve canal and the tooth itself is healthy enough to leave the roots behind. It is not suitable when the roots are infected, when the tooth is very mobile, or when the tooth lies in a position where the crown cannot be removed without disturbing the roots. Left-behind roots sometimes move slowly towards the surface over the following years and occasionally need removing later, by which time they have often moved away from the nerve.

Whether a coronectomy, a full extraction or monitoring is the right approach is a surgical judgement made for your tooth, and you should have the reasons explained before you decide.

What happens if numbness does not wear off?

Contact the clinic if your lip, chin or tongue is still numb the day after surgery. Early review matters: the surgeon records exactly which area is affected and how it feels, so changes can be measured at follow-up visits. Simple tests of light touch and sharp and blunt sensation are repeated over the following weeks.

Most nerve injuries after wisdom tooth removal are bruising or stretching of the nerve rather than a cut, and feeling returns gradually, often first as tingling or pins and needles. Improvement can continue for many months. If numbness is not improving as expected, the surgeon explains the options, which can include referral for specialist assessment.

While feeling is reduced, protect the area: test the temperature of drinks with your hand or the other side of the mouth, be careful when shaving or applying make-up on the chin, and take small bites to avoid biting the lip or tongue. Eating and speaking usually adapt quickly even when some numbness remains.