In short. The workhorse horizontal-advancement osteotomy of the chin: how the bone is moved and fixed, what the nerve dictates, and honest recovery timelines.
Key points
- Advancement improves projection and the neck-chin angle; adding downward movement lengthens a short lower face but predictably widens the chin’s appearance, so width is planned for.
- Setback narrows an over-projected chin.
- Small sideward shifts correct asymmetry.
Sliding genioplasty is the classic bone operation for a recessed chin: a horizontal cut below the tooth roots and the nerve canal frees the chin segment, which slides forward (or downward-forward, backward, or to one side) and is fixed with a plate. The bony gap fills in as it heals, making the new position permanent — your own bone, moved, rather than something resting on it.
The anatomy that dictates the cut
The inferior alveolar nerve runs a canal through the mandible and emerges at the chin to supply sensation to the lower lip. The osteotomy is planned on x-ray imaging to pass safely below the canal and the tooth roots — typically several millimeters of margin. Advancing the segment also brings the soft tissue of the chin forward with it, which is why the profile change is more than the millimeters suggest.
Who it suits — and who it does not
It suits moderate-to-severe chin deficiency, vertical shortening or lengthening, and asymmetry — the situations an implant cannot honestly correct. It is not the operation for a whole-jaw recession with a disturbed bite (that is orthognathic surgery), nor for patients unwilling to accept general anesthesia, several weeks of swelling, and a period of lip numbness.
The options compared
Movement choices, made on the table
Advancement improves projection and the neck-chin angle; adding downward movement lengthens a short lower face but predictably widens the chin’s appearance, so width is planned for. Setback narrows an over-projected chin. Small sideward shifts correct asymmetry. Conservative advancement preserves a natural male or female chin character; over-advancement creates the operated, jutted look that no one wants.
Incisions and anesthesia
Everything happens through an incision inside the lower lip; there is no external scar. The operation takes one to two hours under general anesthesia, with a day-case or one-night hospital stay and standard hospital-grade monitoring.
What surgery can and cannot achieve
It delivers durable, three-dimensional correction of chin position — permanently. It cannot sharpen the jawline along its whole length, correct a bite, or remove submental fullness; those are separate procedures that may be staged with it.
Recovery and downtime
Expect pronounced lip and chin swelling for one to two weeks, a soft diet and antiseptic rinses for several weeks, and gradual return to normal food. Lower-lip numbness or altered sensation is nearly universal early on and usually improves steadily over weeks to months. Desk work resumes in one to two weeks; sports wait about six weeks.
Complications and revision
Named honestly: infection through the intraoral wound, hematoma, asymmetry, plate irritation, transient or rarely permanent lip numbness, and uncommonly a nonunion where the shifted segment fails to fuse — managed by re-fixation. Cosmetic revision, when genuinely needed, waits at least a year.
Preparation and long-term follow-up
Preparation means imaging to map the nerve canal, dental review when indicated, and photographic planning agreed with you before surgery. Bone healing is judged over three to six months, and final contour at a year — follow-up runs that full arc.
Arrange a surgical review if
- Lip numbness is total, worsening, or still dense after the early weeks — the nerve needs assessment.
- Fever, foul drainage, or progressive swelling suggests infection of the intraoral wound or bone.
- The chin segment moves or clicks — fixation failure is corrected early, not watched.
Frequently asked questions
Why does the nerve canal dictate where the cut is made?
The inferior alveolar nerve runs through a canal in the mandible and emerges at the chin to supply sensation to the lower lip. The osteotomy is planned on x-ray imaging to pass safely below the canal and the tooth roots, typically with several millimeters of margin.
Does moving the bone forward change more than the bone itself?
Yes. Advancing the segment also brings the soft tissue of the chin forward with it, which is why the profile change is more than the millimeters suggest. The bony gap fills in as it heals, making the new position permanent.
Will my lower lip be numb afterwards?
Lower-lip numbness or altered sensation is nearly universal early on and usually improves steadily over weeks to months, though it can rarely be permanent. Numbness that is total, worsening, or still dense after the early weeks needs assessment, because the nerve is the structure most at risk.
Risks & Limitations
- Bruising and swelling lasting weeks; after bone surgery, months pass before the final result is visible.
- Scars are permanent. They mature and fade over 6–12 months but never disappear.
- Numbness or altered sensation, which may be temporary or, after bone or nerve work, lasting.
- Asymmetry, under-correction or over-correction; final assessment is made at 6–12 months.
- Infection, bleeding or haematoma, which may need drainage or antibiotics.
- Breathing changes after nasal surgery, which may be temporary or require further treatment.
- Revision surgery carries higher risk and is less predictable than a first operation.
When to Seek Care
- Difficulty breathing or shortness of breath — seek emergency care immediately.
- Rapidly expanding swelling, or a tense, painful, tight area.
- Fever above 38 °C, spreading redness, warmth or pus.
- Bleeding that does not stop with gentle pressure.
- Any sudden change in vision after facial surgery or a facial injection.
References & Further Reading
- American Society of Plastic Surgeons (ASPS) — procedure and safety guidance
- International Society of Aesthetic Plastic Surgery (ISAPS)
- National Institute for Health and Care Excellence (NICE, UK) — relevant guidance
- Cochrane Library — systematic reviews in facial plastic surgery
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.