Bimaxillary
osteotomy.
A bimaxillary (or maxillo-mandibular) osteotomy combines a Le Fort I osteotomy and a sagittal split osteotomy of the mandible in a single operation, to reposition both jaws at the same time. It is indicated when both jaws are involved, or when correcting one jaw requires adjusting the other to achieve an optimal bite. It is the most frequent situation in orthognathic surgery.
Bimaxillary osteotomy.
Large discrepancy between the jaws, severe class II or class III.
Facial asymmetry.
Open bite (the front teeth do not touch) with a receding mandible.
Vertically long face.
Obstructive sleep apnoea: bimaxillary advancement is the reference surgical treatment, with a success rate above 85%.
They are functional, with an aesthetic impact:
a normal relationship between the teeth and normal chewing, which prevents long-term tooth wear, gum recession and jaw joint problems;
better speech;
a lower risk of sleep apnoea;
facial harmony, from the front and in profile. Sharing the movement between the two jaws gives a more balanced profile and a more stable result.
All incisions are inside the mouth: on the gum above the upper teeth for the maxilla, and outside the lower molars on each side for the mandible. There is no skin incision. The maxilla is repositioned first using the first 3D-printed surgical splint, then the mandible is brought into occlusion with it using the final splint. Both jaws are fixed with titanium mini-plates and screws, and the incisions are closed with dissolving stitches. A genioplasty is often performed at the same time.
Duration: about 3 hours.
Hospital stay: 1 night, sometimes 2.
Swelling is more marked than after a single osteotomy, unpredictable and variable from one person to another, peaking on days 3–4.
Combined numbness: lower lip, chin and lower incisors on the mandibular side; upper lip, side of the nose, upper teeth and palate on the maxillary side. It recovers over weeks to months; permanent loss of sensation is rare.
Blocked nose for the first few days; do not blow your nose during recovery.
Return to work: 2 to 3 weeks.
Guide to the first 6 weeks on the orthognathic surgery page. Liquid diet in the first week, then blended or minced food for 5 to 6 weeks; maxillofacial physiotherapy from the 3rd week if needed; orthodontic treatment resumes at around 6 weeks, for about 8 months.
The questions
we hear most often.
Why operate on both jaws if only one seems out of place?
Moving a single jaw has limits in terms of stability and aesthetics. Sharing the movement between the two gives a more balanced profile and a more stable result.
Will my face change a lot?
Proportions are harmonised; the identity of the face is preserved. Aesthetic expectations are discussed during the consultation, based on the 3D planning.
Can the chin be corrected at the same time?
Yes, a genioplasty is often performed during the same operation.
Do the plates stay in?
Yes, under the gum, invisible, usually for life. They are only removed if they cause discomfort or if the patient wishes, from 6 months onwards; this is very rare.
Is a bimaxillary osteotomy reimbursed?
Yes, on INAMI/RIZIV functional criteria, like the other osteotomies.
Book an appointment.
Erasme Medical Center, Route de Lennik 900, 1070 Anderlecht — 02 555 37 91 — cons.stomato.erasme@hubruxelles.be
Consultations at Erasme are exclusively dedicated to orthognathic surgery. Please bring your orthodontist's letter and your recent X-rays.