Maxillary Impaction Does Not Negatively Affect the Nasal Airway: A Systematic Review With Meta-Analysis.

PURPOSE: Le Fort I maxillary impaction is an orthognathic surgical procedure to reposition the maxillary complex superiorly. The objective of this study is to investigate if maxillary impaction negatively affects the nasal airway. METHODS: A systematic review with meta-analysis was performed to investigate the effects of maxillary impaction on the nasal cavity. PubMed, Embase, and Cochrane Library databases were accessed. Observational studies, nonrandomized, and randomized controlled trials were included if Le Fort 1 maxillary impaction and nasal airway outcomes assessments were performed. Studies were excluded if maxillary impaction or nasal airway outcome assessment was not performed or if the study included patients with cleft or craniofacial syndromes, previous nasal surgeries, or active respiratory tract. The demographic data, study methodology, magnitude of maxillary impaction, and outcomes related to the nasal airway were collected. These outcomes includes anatomical changes (evaluated by rhinoscopy, acoustic rhinometry, and computed tomography), changes to nasal airflow and resistance (evaluated by rhinomanometry) and changes to quality of life. RESULTS: The search yielded 7517 studies. Ten studies were included after the application of the selection criteria. A total of 126 patients underwent pure maxillary impaction, 97 underwent maxillary impaction and advancement, and 12 had impaction with setback. Despite that maxillary impactions decreased the nasal cavity volume by +21.7%, the cross-sectional area of the narrowest parts of the cavity was only reduced by -8.4%. Maxillary impactions generally increases the nasal airflow (+12.6%) while reducing nasal resistance (-20.2%). Rhinoscopies also showed a reduction in nasal obstruction. CONCLUSION: Maxillary impaction did not negatively affect the nasal airway. The surgeries did not lead to the reduction of the cross-sectional area at the strictures of the nasal cavities. The nasal airflow and resistance was not decreased and increased, respectively. The quality of life of the patients was also not shown to have worsened.