The role of maxillary impaction for nasal breathing. A systematic review and metanalysis

Trabajo fin de Máster de Formación Permanente en Rinología Avanzada y Base de Cráneo Anterior (2023-24). Tutor: Dr. Christian Calvo Henríquez. OBJECTIVE: patients with altered facial growth, particularly those with upper maxillary retrusion, have increased nasal resistance. Correction of these discrepancies often involves anterior, inferior, or superior repositioning of the maxilla. When the maxilla is repositioned superiorly, the elevation of the nasal floor results in a decrease in volume of the nasal cavity. This consequence resulted in the critique of the early Le Fort I osteotomy. Available evidence questions the existence of any negative effect of nasal breathing after maxillary impaction. In this systematic review and meta-analysis, we aim to answer the question of the effect of maxillary impaction in nasal ventilation. METHODS: Pubmed (Medline), the Cochrane Library, EMBASE and Trip Database were checked by two authors from the Rhinology Study Group of the YO-IFOS. Four authors extracted the data. The outcome assessed was any evaluation of nasal breathing, both subjective (questionnaires) and objective (rhinomanometry, rhinohygrometry, fluid dynamics simulation, peak nasal inspiratory flow), as well as the measurement of nasal. RESULTS: A total of 9 studies (196 patients) met inclusion criteria. The data pooled in the meta-analysis reveals a statistically significant reduction of nasal volume of -9.44% after maxillary impaction alone for four uncontrolled studies. Regarding the changes in nasal resistance, maxillary impaction alone for two studies revealed a significant mean reduction -36.97, and -16.51%for two studies performing impaction with maxillary advancement. CONCLUSION: available evidence suggests that maxillary impaction is associated with a reduction in nasal volume and simultaneously with improving nasal resistance and nasal airflow.