Morphometric analysis of nasal cavity volume following Le Fort I maxillary osteotomy

Abstract

Le Fort I osteotomy is a surgical technique used in orthognathic surgery to reposition the maxilla based on the diagnosis of the skeletal deformity. The maxilla is the base of the nasal cavity, and any surgical movement could lead to changes to the volume of the nasal cavity. There is very limited evidence on the impact of different maxillary surgical movements on the nasal cavity volume alone. This study aims to analyze the threedimensional changes in the nasal cavity following Le Fort I osteotomy based on the different types of vectors of maxillary movement and magnitude. Preoperative and postoperative cone beam computed tomography (CBCT) data and surgical records were obtained based on our inclusion and exclusion criteria. 3D medical imaging software was used to analyse the changes to the nasal cavity. The study found there is an increase in nasal cavity volume if the vector of movement was a combination of down graft with advancement (p<0.05) and if a pure down graft (p>0.05). There was a reduction in nasal cavity volume when the maxillary vector of movement was purely forward or in a combination of backward and impaction or a vector of impaction (p<0.05) and a vector combination of advancement with impaction (p>0.05). No correlation was found between the surgical magnitude changes ratio and the nasal cavity volume changes ratio in all the groups. In conclusion, this study brings forward a clinical consideration that needs to be included when assessing expected individual changes to nasal resistance when performing the Lefort I osteotomy besides the expected skeletal and occlusal changes.