A numb lip or chin after Dental treatment is common for a few hours while the local anaesthetic wears off. Numbness that lasts beyond that, or follows an extraction, an implant or a deep lower-jaw procedure, needs a call to your Dentist the same day. A scan is sometimes useful, but it is the Dentist's decision and not the first step.
Most numbness after an injection fades on its own. A small number of people notice that the lip, chin, tongue or teeth stay numb, tingly or oddly sensitive for days or longer. This guide explains the common causes, how long recovery can take, what to do and where imaging fits. It does not diagnose the cause in any one person, and a Dentist who has examined you is the right person to do that.
What Is Normal and What Is Not
| What you notice | Usually means | What to do |
|---|---|---|
| Numb lip or cheek for a few hours after an injection | Local anaesthetic wearing off. Expect it to fade within a few hours | Avoid biting or hot drinks until it fades |
| Still numb the next day | May be a nerve irritated by the injection or the procedure | Call your Dentist the same day. Do not wait to see |
| Numb chin or lip after a lower tooth extraction, an implant or surgery | The nerve that runs through the lower jaw may be bruised or affected | Call your Dentist promptly |
| Tingling, burning, electric-shock feelings or altered taste | Nerve irritation or injury | Call your Dentist and describe it exactly |
| Numbness with swelling, fever or a bad taste | Possible infection | Contact your Dentist the same day |
Typical duration of local anaesthetic varies by drug and dose; confirm the wording with a Dentist.
Why It Can Happen
The nerve that supplies the lower lip and chin, the inferior alveolar nerve, runs inside the lower jaw in a canal, and a branch leaves the bone at the chin. A second nerve to the tongue runs close to the lower wisdom tooth. A review of nerve injury in dentistry lists these causes [1]:
Needle injury or bruising from a local anaesthetic injection. The needle can touch the nerve or cause bleeding around it.
Implant placement. A drill or implant that enters or presses on the canal can injure the nerve.
Surgery or extraction near the canal, including lower wisdom teeth, where swelling, pressure or the procedure itself can affect the nerve.
Infection or heat. Inflammation near the canal, or heat produced during drilling, can damage the nerve.
Chemicals used in the procedure. For example, irrigating solutions that reach the nerve.
Some people are at more risk than others. The same review lists older age, female sex, immediate implant placement after extraction and low-density bone in the back of the lower jaw as factors, and notes that reported injury rates vary widely between studies [1]. These are general patterns, not a prediction for you.
How Long Can Recovery Take?
Recovery depends on how badly the nerve was affected. As a general guide from the same review:
A bruised nerve often recovers within days to about a week, sometimes one to two months.
A more significant injury can take two to four months, and improvement can continue for up to about a year.
If there is no recovery after several months, the change may be permanent, and early review matters because some options work best if used early.
The practical lesson is to report numbness early. Dentists can test sensation, track change over weeks and refer to a specialist if recovery stalls. Waiting weeks before mentioning it can narrow the options.
Where Imaging Fits
A scan does not treat numbness, and it is not always needed. It is used to answer a specific question your Dentist or Oral Surgeon has, for example:
Is an implant or a root tip close to, or inside, the nerve canal?
Is there infection, a cyst or another lesion near the canal?
Was the canal in an unusual position that the earlier X-ray did not show?
Are the cortices of canal intact?
Is there any asymmetry in the course of canal?
A flat X-ray shows the canal only in two dimensions. A 3D scan shows where it runs in relation to the teeth and implants, which a flat image cannot. Mandibular canal and mental foramen variations explains why the canal is not in the same place in everyone, and CBCT scanning in dentistry: a complete guide explains what the 3D scan shows. A scan has to be requested by a Dentist, because the timing and field depend on the question and the dose should have a reason.
What to Do If Your Lip or Chin Is Still Numb
Call the Dentist who treated you the same day, even if the clinic has closed. Many have an emergency number.
Describe exactly where and how it feels: numb, tingling, burning, or changed taste.
Note when it started, and whether it is improving, staying the same or spreading.
Do not chew on the numb side, and avoid very hot food until sensation returns.
Keep every follow-up visit. Sensation is usually tested at intervals.
If you are told a scan may help, ask what question it answers and which area it will cover.
When It Is an Emergency
Numbness of the face with sudden weakness on one side, drooping of the face, trouble speaking, or sudden vision loss needs emergency medical care straight away. Swelling that makes it hard to breathe or swallow, with fever, also needs emergency care. These are not routine Dental follow-ups.
Frequently Asked Questions
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Usually a few hours, as the local anaesthetic wears off. If it is still numb the next day, call your Dentist.
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Rarely, yes. The needle can irritate or injure a nerve. Most cases recover, but any numbness that outlasts the anaesthetic should be reported early.
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It can, if the implant or drill comes close to or enters the nerve canal. Tell your Dentist straight away, because early action matters.
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A scan shows bone, canals, teeth and implants, not the nerve itself. It can show whether an implant or a root is close to the canal or if the canal cortices are intact.
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Often it does, over days to months, but it should be reported to your Dentist early so that sensation can be followed.
