Numbness After Wisdom Teeth Removal — How Long Is Normal?

Understanding Numbness After Wisdom Tooth Extraction

Numbness after wisdom tooth removal has two distinct causes: the local anaesthetic used during the procedure (which wears off within 2-5 hours) and, far less commonly, nerve involvement during extraction (which may persist for weeks to months). Research published in the British Journal of Oral and Maxillofacial Surgery found that temporary nerve disturbance occurs in 1-5% of lower wisdom tooth extractions, while permanent nerve injury affects only 0.1-0.5% of cases. The inferior alveolar nerve and the lingual nerve — both of which pass in close proximity to the roots of lower wisdom teeth — are the two nerves most commonly affected. Understanding the difference between normal anaesthetic numbness and potential nerve involvement helps you know when to seek professional assessment. At Townsville Dental Clinic, we use digital X-rays and CBCT imaging where indicated to assess nerve proximity before extraction and minimise the risk of nerve injury.

Anaesthesia Numbness: The Normal Timeline

Local anaesthesia is essential for a comfortable wisdom tooth extraction. Here is what to expect as it wears off:

Types of Anaesthesia and Duration

The duration depends on the specific anaesthetic used, the amount administered, and individual factors such as your metabolism and blood flow to the area. Lower wisdom teeth require an inferior alveolar nerve block, which numbs the entire lower jaw, lip, and chin on that side — this tends to last longer than the infiltration technique used for upper teeth.

What to Expect While Numb

• Your lower lip, chin, and tongue (for lower wisdom teeth) or upper lip and cheek (for upper wisdom teeth) will feel thick, heavy, or absent
• You may have difficulty speaking clearly or controlling saliva
• Do not eat until sensation returns — you risk biting your lip, tongue, or cheek without realising it
• Avoid hot drinks that could burn numb tissue

Nerve-Related Numbness: When It Lasts Longer

If numbness persists beyond the expected anaesthesia duration (generally 8 hours or more), the nerve itself may have been affected during extraction. This is an uncommon but recognised complication of lower wisdom tooth removal.

The Two Nerves at Risk

Inferior alveolar nerve (IAN): Runs through a canal inside the lower jawbone, directly beneath the roots of lower wisdom teeth. Injury causes numbness or altered sensation in the lower lip, chin, and lower gums on the affected side.

Lingual nerve: Runs along the inner surface of the lower jaw, close to the lower wisdom teeth. Injury causes numbness or altered sensation in the front two-thirds of the tongue on the affected side, which may also affect taste perception.

How Nerve Injury Occurs

• Direct trauma during surgical extraction if the nerve is in close proximity to the tooth roots
• Compression from swelling in the nerve canal
• Stretching of the nerve during retraction of tissue
• Proximity of roots to the nerve canal — when roots curve around or contact the nerve, the risk increases significantly

Recovery Timeline for Nerve Numbness

A study published in the Journal of Oral and Maxillofacial Surgery analysing over 4,000 wisdom tooth extractions found that the rate of temporary nerve disturbance was 3.6% for the inferior alveolar nerve and 1.1% for the lingual nerve, with the vast majority resolving within 6 months.

Tips for Managing Numbness

While waiting for anaesthesia or nerve sensation to return:

• Avoid eating until anaesthetic numbness resolves to prevent accidental biting injuries
• Be careful with hot drinks — numb tissue cannot sense temperature and can be burnt
• Check your face in a mirror before going out, as drooling may occur without you noticing
• If nerve numbness persists, be mindful when eating and drinking as you may need to chew on the unaffected side and drink carefully to avoid spills

When to Contact Your Dentist

Seek professional assessment if:

• Numbness persists beyond 8 hours after surgery (exceeding normal anaesthesia duration)
• Numbness returns after initially resolving
• You cannot feel your lower lip, chin, or tongue the day after surgery
• You are biting your lip or tongue during eating without feeling it
• Loss of taste on one side of the tongue

Early documentation of nerve disturbance is important because it establishes a baseline for monitoring recovery and determines whether specialist referral to an oral and maxillofacial surgeon is warranted.

Related Services

• Wisdom Teeth Removal
• Wisdom Tooth Extraction Complications
• Tooth Extractions

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Sources: British Journal of Oral and Maxillofacial Surgery; Journal of Oral and Maxillofacial Surgery; International Journal of Oral and Maxillofacial Surgery.