Phẫu thuật le fort ii kết hợp le fort i và bsso điều trị sai khớp cắn loại iii trên bệnh nhân khe hở môi – vòm miệng Combined Le Fort ii, Le Fort i, and BSSO for cleft-related skeletal class iii deformity

Le Fort I osteotomy is one of the most commonly performed procedures in orthognathic surgery. It allows the tooth-bearing maxilla to be repositioned in three dimensions and can therefore address a wide range of skeletal and occlusal discrepancies.

In some patients, however, particularly those with congenital craniofacial deformities, the deficiency is not confined to the tooth-bearing maxilla. Instead, hypoplasia may involve the entire nasomaxillary complex.

In such cases, a conventional Le Fort I advancement alone may not adequately address the facial deformity.

Midfacial deficiency in a patient with cleft lip and palate

The patient was a 20-year-old woman with a history of cleft lip and palate who presented with a severe skeletal Class III deformity associated with significant midfacial hypoplasia.

Clinical and three-dimensional assessment demonstrated that the deficiency predominantly involved the nasomaxillary complex, while the zygomatic and orbital regions were relatively well developed.

This distribution of the deformity was a critical factor in determining the appropriate level of osteotomy.

If a conventional Le Fort I advancement had been performed alone, the tooth-bearing maxilla could have been advanced into an appropriate relationship with the mandible. However, the nasal complex and the midface above the Le Fort I level would have remained relatively retruded.

The result could therefore have been an improved occlusion without adequate correction of the midfacial deficiency, potentially making the discrepancy between the advanced maxilla and the retruded nasal region even more apparent.

The objective of surgery was therefore not simply to correct the bite, but to restore a more harmonious relationship of the entire midface.

Why Le Fort II?

Unlike a Le Fort I osteotomy, a Le Fort II osteotomy is positioned at a higher level and allows the nasomaxillary complex to be advanced as a unit.

Because the patient's zygomatic and orbital regions were relatively well developed, a Le Fort II osteotomy allowed the operation to specifically address the deficient nasomaxillary region without unnecessarily mobilizing the entire upper midface.

Following discussion of the surgical strategy with Professor Imad Abu El-Naaj, I elected to combine three osteotomies:

A Le Fort II osteotomy was used to advance the nasomaxillary complex.

A Le Fort I osteotomy was incorporated to provide additional control of the tooth-bearing maxilla, allowing further refinement of the skeletal and occlusal relationship.

A bilateral sagittal split osteotomy (BSSO) was performed in the mandible to reposition the lower jaw according to the new maxillary position and establish the intended occlusion.

The combination of Le Fort II and Le Fort I allowed different components of the midface to be repositioned by different amounts rather than requiring the entire region to move as a single unit.

Three-dimensional surgical planning

Because of the complexity of the osteotomies and skeletal movements, the entire procedure was planned preoperatively in a three-dimensional virtual environment.

Using the patient's imaging data, the osteotomy lines and intended postoperative positions of the individual skeletal segments were simulated before surgery. This allowed the relationship between the nasal complex, maxilla, mandible, and occlusion to be evaluated before transferring the plan to the operating room.

Once the surgical plan had been finalized, patient-specific cutting guides and temporary positioning guides were designed according to the patient's individual anatomy and manufactured using metal 3D printing.

The cutting guides were used to transfer the planned osteotomy lines accurately to the surgical field.

Following mobilization of the skeletal segments, the patient-specific positioning guides were used to reproduce the planned postoperative skeletal positions.

Importantly, in this technique the patient-specific positioning devices served only as temporary intraoperative guides. Once the intended skeletal position had been established and verified, they were removed and replaced with conventional commercially available fixation plates and screws.

In this way, patient-specific technology was used to transfer the virtual surgical plan to the operating room without requiring permanent patient-specific fixation implants.

Beyond correction of the occlusion

In patients with congenital craniofacial deformities, successful orthognathic surgery cannot be defined solely by achieving a Class I dental relationship.

A satisfactory occlusion with persistent midfacial deficiency does not represent complete correction of the deformity.

The level of osteotomy should therefore be selected according to where the skeletal deficiency actually exists within the face. When the deformity is primarily dentoalveolar or maxillary, a Le Fort I osteotomy may be sufficient. When the deficiency extends superiorly into the nasomaxillary complex, a higher-level osteotomy such as Le Fort II may need to be considered.

Following surgery, the patient's maxillomandibular relationship and midfacial projection were substantially improved, and both the patient and her family were satisfied with the outcome.

Because this was a complex congenital craniofacial deformity, orthognathic surgery represented one component of a longer reconstructive pathway. Additional procedures may still be required to further refine facial form and function.

According to our team's records at the time of surgery, this was the first Le Fort II osteotomy performed at the National Hospital of Odonto-Stomatology, Hanoi. It was also a particularly challenging case combining Le Fort II, Le Fort I, and BSSO with three-dimensional virtual surgical planning and patient-specific surgical guides.