Numbness that has not gone away after surgery

Local anaesthetic wears off on a schedule. Depending on the agent used and whether a vasoconstrictor was included, ordinary numbness from the injection lasts somewhere between two and eight hours, and long-acting agents used for post-operative comfort can extend that towards twelve. Waking the next morning with normal sensation is the usual course after a lower wisdom tooth removal.

Numbness that is still present the following day is a different thing, and it is worth naming clearly rather than waiting to see. It means the nerve itself was affected during the procedure — most often the inferior alveolar nerve, which supplies the lower lip and chin on that side and runs in a canal through the lower jaw close to the roots of lower third molars, or the lingual nerve, which supplies the side of the tongue and runs in soft tissue on the inner side of the jaw.

Being affected is not the same as being cut. The overwhelming majority of these events are bruising, stretching or compression of a nerve that remains structurally continuous, and nerves in that state recover. Reported rates of temporary altered sensation after lower third molar surgery sit in the low single-digit percentages, while permanent change is markedly rarer. The odds are strongly in favour of recovery, and that is worth holding onto during a period which is genuinely unsettling.

Two vocabularies get used in this conversation and they describe different things. One describes what you feel. The other describes what happened to the nerve. Knowing which is which makes the conversation considerably easier to follow.

For what you feel: paraesthesia is altered sensation, the tingling or pins-and-needles quality. Anaesthesia is absent sensation, complete numbness. Hypoaesthesia is reduced sensation. Dysaesthesia is altered sensation that is unpleasant — burning, or pain in response to light touch — and it is the one that deserves particular attention, because it responds differently to management and it affects quality of life more than simple numbness does.

For what happened: neurapraxia is a conduction block in a nerve that is anatomically intact, and it recovers, typically within days to a couple of months. Axonotmesis is damage to the fibres within an intact sheath, and it recovers slowly as fibres regrow at roughly a millimetre a day, which is why recovery over months rather than weeks is still a normal picture. Neurotmesis is disruption of the nerve itself, and it is the category that does not resolve without intervention.

Nobody can tell you on day two which of the three you have. The categories are distinguished by watching what happens over time, which is the reason the follow-up schedule looks the way it does and the reason nothing is decided immediately.

Recovery from nerve injury does not proceed evenly and it is not felt as a percentage. It tends to arrive as a change in quality — numbness becoming tingling, tingling becoming uncomfortable, an uncomfortable patch becoming smaller. Patients frequently describe the intermediate stage as feeling worse, and it is generally a sign of regeneration rather than deterioration.

The three-month mark is not arbitrary and it is not merely a convention of scheduling. It is the point by which a nerve that was going to recover on its own has usually shown convincing evidence of doing so, and it is early enough that surgical repair, where repair is appropriate, is still most likely to succeed. Outcomes after nerve repair are consistently reported as better when the repair happens earlier, and the practical window that most microneurosurgical services describe closes over the following months.

That is why a review at three months matters more than it appears to. It is not a formality to confirm progress. It is the appointment at which a referral either happens or does not.

There is no single deadline after which nothing can be done, but there is a strong and well-documented relationship between how early a repair happens and how well it works. A nerve left disconnected for a long period develops scarring at the injury site, and the muscle and skin it supplies gradually lose the capacity to respond. Repairing later means repairing into less receptive tissue.

The problem this creates is a mismatch between how the injury feels and how the clock behaves. Numbness is not painful. It is inconvenient — food and drink escape without being noticed, lipstick goes on unevenly, shaving is awkward, kissing feels strange — and inconvenience is easy to adapt to. Patients adapt, months pass, and the window narrows without anything having felt urgent at any point. That is the specific failure mode worth guarding against, and it is why the dates deserve to be written down rather than held loosely.

The equivalent question for a patient to ask is not "will this get better", which nobody can answer honestly at week two. It is "what date are we reviewing this, and what happens at that appointment if nothing has changed". A clear answer to the second question is what keeps the timetable from drifting.

The most useful thing a patient can do in this situation is keep an ordinary record. Recovery is judged by comparison, and comparison needs two measurements. A clinician who sees you at three months with a written trail of what the area was like at week one, week four and week eight has evidence of a trajectory; the same clinician with only today's examination and your recollection has a snapshot.

1. Draw the numb area on a simple outline of your face or tongue and date it — a rough sketch is genuinely sufficient
2. Repeat the drawing weekly for the first month, then monthly, keeping every version rather than updating one
3. Note the quality each time: completely numb, tingling, burning, uncomfortable to touch, or normal
4. Record anything that changed, including whether the area got smaller or the sensation altered in character
5. Photograph the drawings so they are dated automatically and cannot be lost
6. Note practical effects — dribbling, biting the lip or tongue, difficulty with speech or eating
7. Keep the operative note, the radiographs and any cone-beam scan in the same folder

Two practical points alongside the record. Take care with hot food and drink and with chewing on the affected side, because an area you cannot feel is an area you can burn or bite without noticing, and repeated lip or tongue trauma is a common and avoidable secondary problem. And if the sensation is not merely absent but unpleasant — burning, or pain from light touch — say so explicitly rather than describing it as numbness, because that presentation is managed differently and it changes the urgency of assessment.

Waiting is uncomfortable advice to receive, particularly for a symptom that is present every waking minute, and it is reasonable to want something to do. Some of what gets suggested has a genuine rationale and some of it does not, and it is worth being able to tell them apart.

Protecting the area has a clear rationale. Skin and mucosa you cannot feel are vulnerable to burns from hot drinks and to repeated trauma from chewing, and a lip bitten repeatedly over several weeks develops a problem of its own on top of the original one. Checking the area in a mirror rather than by feel, taking care with temperature, and being deliberate about which side you chew on are all straightforwardly useful.

Sensory re-education — light, structured stimulation of the affected area, usually with a soft brush or fingertip, done consistently for short periods each day — is used in some services during recovery and after repair. The evidence base is modest rather than absent, and it does not accelerate nerve regrowth itself; the argument is about how the brain interprets the signals that do arrive. It is low-risk and cheap, and it is worth asking whether it is being recommended in your case rather than starting an improvised version.

Where the sensation is painful rather than merely absent, there are medicines used specifically for nerve-related pain that are different from ordinary painkillers, and ordinary painkillers tend to disappoint in this situation. That is a conversation to have promptly rather than to endure, and it does not require waiting for the three-month review.

What does not have a rationale is worth naming too. Vitamin supplements, laser treatments sold directly to patients, and various devices are marketed for nerve recovery without convincing evidence behind them, and a patient in a frightening situation is exactly the audience such things are aimed at. Spending money on them is not neutral if it delays the review that actually matters.

Nerve repair after dental surgery is a subspecialty. It is performed by oral and maxillofacial surgeons who have specific microneurosurgical training and who do this work regularly, usually within a hospital or university service with the operating microscope and the theatre time it requires. It is not a routine part of a third molar practice, and this one does not perform it.

That distinction is worth stating plainly, because the surgeon who did the original operation is not the natural person to assess whether a repair is warranted. Not through any lack of competence, but because the assessment involves judging their own work, and a patient in that position deserves an independent opinion as a matter of course rather than as a complaint. Asking for a referral is not an accusation, and a surgeon who treats it as one is telling you something.

What you should expect from the practice that operated is straightforward: prompt acknowledgement, an accurately recorded onset date, review at sensible intervals with documented mapping, the complete records and imaging released on request, and a referral made at the three-month mark if the picture has not substantially improved. If a referral is not being offered by then, ask for one directly, and ask for it in writing.