In short. Numbness of the lower lip and chin is the risk both operations carry, and it should be discussed in the same terms for each rather than as the problem of one.
Key points
- A patient considering either operation should hear that numbness is possible, that it usually improves, that it can be lasting, and what happens if it does not return.
- Being told this about one operation and not the other is a sign the comparison is being made for you.
Numbness of the lower lip and chin is the risk these two operations share, and it is the one patients most often mention afterwards. It is discussed here in the same terms for both, because the nerve that supplies that sensation is in the region both operations work in.
Why the nerve is at risk
The nerve that carries sensation from the lower lip and the chin runs through the jawbone and emerges near the chin before branching into the soft tissue. A bone operation works on the bone the nerve passes through. A device operation works in the pocket created in front of the bone. The two approach the same region from different directions, and neither can be described as avoiding the nerve.
What the numbness feels like
Patients describe a reduced or altered sensation rather than an absence of it more often than not: a patch of the lower lip or chin that feels numb, or tingling, or as though it belongs to someone else. It can affect the lip on one side, or the chin, or both, and it can change over the weeks after the operation. It is different from the swelling that is expected.
The same risk, stated the same way
A patient considering either operation should hear that numbness is possible, that it usually improves, that it can be lasting, and what happens if it does not return. Being told this about one operation and not the other is a sign the comparison is being made for you.
How it is followed up
Sensation is tested at reviews rather than left to the patient to report, and an area that is not recovering is assessed rather than watched indefinitely. Where it is altered for longer than expected, what has changed is documented and reviewed over time. Most patients find that it improves gradually, and the improvement is measured in months rather than days.
The other risks, in the same breath
Both operations also carry bleeding, infection, an unsatisfactory contour or asymmetry, and the risks of a general anaesthetic. The bone operation adds the risks of cutting and healing bone, including problems with the way the segment heals. The device operation adds the risks of a foreign body that is intended to stay, including movement and the possibility of removal. Neither list is short, and they are different rather than unequal.
What to establish before consenting to either
- That numbness has been described to you in the same terms for both operations, not as one side’s problem.
- What the plan is if sensation does not return, and who follows it up rather than leaving it to you to raise.
- Which risks belong to the operation proposed and which would apply to the other, so the comparison is yours to make.
Numbness is not a reason to refuse both operations. It is a reason to know which operation is being proposed, why, and what happens if the sensation does not come back. A patient who has been told all three is in a position to decide.
Frequently asked questions
Is numbness after chin surgery permanent?
In most people it improves over weeks to months, and in a proportion it does not fully return. That is why it belongs in the consent conversation for both operations rather than being mentioned as an afterthought. Reduced rather than absent sensation is more common than complete numbness.
Is numbness more likely with one of the two operations?
Neither operation can be described as free of the risk, and the honest position is that the nerve is at risk in both because both work in the same region. What differs is the route taken to reach it. Any claim that one operation avoids the nerve altogether should be treated with scepticism.
What should I do if sensation does not return?
Report it rather than waiting quietly, and ask at the review what the examination found and what the plan is. If it persists, it should be assessed rather than assumed to be permanent. Persistent altered sensation is managed, and it is a reason to keep attending follow-up.
Risks & Limitations
- Every operation carries risk, and no result can be guaranteed.
- Numbness of the lower lip and chin can follow either operation. It usually improves, and it can be lasting.
- A chin implant may need a further operation to remove or exchange it, and a repositioned bone segment may need further surgery if it does not heal as planned.
- Final results are judged months later, once the swelling has resolved, not in the first weeks.
When to Seek Care
- Difficulty breathing or chest pain — seek emergency care immediately.
- Fever, or spreading redness, warmth or discharge around the incision.
- Bleeding that does not settle with gentle pressure.
- Sensation in the lower lip or chin that is worsening rather than improving, or pain that is increasing.
References & Further Reading
- American Society of Plastic Surgeons (ASPS) — craniofacial and chin surgery guidance
- National Institute for Health and Care Excellence (NICE, UK) — relevant guidance
- Cochrane Library — systematic reviews
- Chinese Medical Association Plastic Surgery Branch — clinical guidance
This page is patient education, not medical advice, and it does not cite individual studies. Discuss your own case with a qualified clinician. To arrange an assessment at Chongqing West District Hospital, see Contact & Consultation.