What Is Lower Jaw Surgery (Mandibular Osteotomy)?
Lower jaw surgery is one of the most common orthognathic procedures. Here is what you should know.
Lower jaw surgery, medically called a mandibular osteotomy or bilateral sagittal split osteotomy (BSSO), is a procedure that repositions the lower jaw (mandible) to correct bite problems and facial imbalances.
- What it corrects:
- Underbite (lower teeth sit in front of upper teeth)
- Overbite (lower jaw is recessed)
- Facial asymmetry of the lower face
- Open bite (in combination with other procedures)
- Sleep apnea caused by a recessed lower jaw
- TMJ symptoms related to jaw position
- How it is done:
- Incisions are made inside the mouth behind the back molars
- The lower jawbone is carefully split on both sides (sagittal split)
- The jaw is moved to its new position (forward, backward, or rotated)
- Tiny titanium plates and screws stabilize the jaw
- Incisions are closed with dissolvable stitches
- Surgery takes 1β2 hours for lower jaw alone
- Hospital stay of 1 night
- You may need to stay in the hospital for observation
- The lower jaw is more mobile than the upper jaw during healing
- Elastic bands help guide the bite into its new position
- Swelling of the lower face and under the chin (peaks at days 2β3)
- Numbness of the lower lip and chin is common β usually improves over 6β12 months
- Liquid diet for 2β4 weeks
- Gradual return to soft foods
- The jaw bone heals completely in 6β8 weeks
What to Expect
Recovery
Clinical Guidance
Lower jaw surgery (mandibular osteotomy) repositions the lower jaw to correct underbite, overbite, asymmetry, and sleep apnea. It is performed through incisions inside the mouth, and temporary numbness of the lower lip is a common but usually resolving side effect.