Sinonasal Morphologic Changes and Patient-Reported Nasal Function After Le Fort I Maxillary Advancement

For many people, the simple act of breathing through the nose can feel like a struggle. When the airway is blocked, it affects sleep, energy, and overall quality of life. While some obstructions are caused by swollen tissues or allergies, others stem from the very shape of the face and jaw. In the field of orthognathic surgery, doctors reposition the upper and lower jaws to correct bite problems and improve facial harmony. One of the most common procedures involves moving the upper jaw, known as the maxilla, forward. Because the nose sits directly on top of this bone, moving the jaw inevitably changes the space inside the nasal cavity. For decades, surgeons have wondered if this movement helps patients breathe better or if it accidentally creates new blockages by twisting the delicate structures inside the nose.

A team of researchers at the Universidade Estadual de Campinas in Brazil set out to answer this question by looking at the long-term results of this specific surgery. They focused on a procedure called Le Fort I maxillary advancement, where the upper jaw is cut and moved forward to correct a receding face. The team wanted to know two things: did the physical shape of the nasal passages change in a way that could be measured, and did the patients actually feel like they could breathe better? To find the answers, they studied sixteen adults who had undergone this surgery, some of whom also had their lower jaws adjusted. The researchers waited at least one year after the operations to ensure the healing was complete before taking new scans and asking the patients how they felt.

To see what happened inside the nose without cutting anyone open, the team used a special type of three-dimensional X-ray called cone-beam computed tomography. They took pictures of the patients before the surgery and again after the recovery period. Using advanced computer software, they superimposed these images to measure the exact volume of the nasal cavity, the space behind the nose called the nasopharynx, and the air-filled pockets known as the maxillary sinuses. They also measured how much the wall dividing the nostrils, the septum, had shifted or bent. Alongside these physical measurements, the patients filled out a questionnaire designed to rate how much trouble they had breathing through their nose, covering issues like congestion, blockage, and difficulty sleeping.

The results painted a clear picture of what the surgery did and did not change. The physical structure of the nasal cavity itself, the main tunnel where air flows, remained largely the same size. The researchers found no significant change in the volume of the nasal cavity or the degree to which the septum was bent. This is a crucial finding because it suggests that moving the jaw forward does not crush or distort the main airway. However, the space directly behind the nose, the nasopharynx, did get noticeably larger. The volume of this area increased significantly, creating more room for air to pass through the back of the throat.

While the main airway stayed stable, the researchers did notice a change in the sinuses, the hollow spaces within the cheekbones. The volume of the right maxillary sinus decreased slightly in the group as a whole. More importantly, in about one-third of the patients, the small opening that drains this sinus became blocked after the surgery, whereas it had been open before. This blockage did not happen to everyone, but it appeared frequently enough to be a notable side effect. Despite this specific change in the sinus drainage, the patients' own reports told a different story about their overall breathing. The scores on the breathing questionnaire dropped dramatically, moving from a moderate level of trouble to almost no trouble at all. The average score improved from 34.4 before surgery to just 10.0 after, indicating that the patients felt a substantial relief in their ability to breathe.

The study concludes that moving the upper jaw forward is a functional success for most patients, providing a significant improvement in how they feel they breathe without ruining the shape of the nasal cavity. The surgery successfully enlarged the space at the back of the nose, which likely contributes to this feeling of relief. However, the findings also serve as a reminder that the surgery is not without risks for every single person. The fact that the sinus opening became blocked in a significant portion of the group suggests that doctors need to keep a close watch on the sinuses long after the surgery is over. Even though patients feel they are breathing better, a routine check of the sinus drainage can help identify those few individuals who might develop a hidden blockage that needs attention. Ultimately, the procedure offers a way to fix the jaw and improve breathing simultaneously, provided the surgeon remains vigilant about the complex changes happening inside the nose.