Orthodontic-surgical treatment and respiratory function: rhinomanometric assessment

Aim: The study was designed to quantitatively assess changes in respiratory function for patients with severe malocclusion and maxillary constriction following combined orthodontic- surgical treatments. Material and methods: The study involved ten patients between the ages of 18 and 30, all scheduled for orthodontic-surgical treatment of maxillary constriction. The participants were divided based on their clinical needs: four patients with transverse hypoplasia between 7 and 9 mm underwent surgically-assisted rapid palatal expansion (SARPE), while six patients with 6 to 7 mm hypoplasia and skeletal class II or III discrepancies underwent a Le Fort I down fracture combined with a bilateral sagittal split osteotomy (BSSO). Respiratory efficiency was evaluated using computerized active anterior rhinomanometry (AAR) and active posterior rhinomanometry (APR) to measure nasal resistance before treatment (T0) and 40 days after surgery (T1). Specifically, all 1o patients received AAR evaluations, while 6 patients received both active anterior (AAR) and active posterior rhinomanometry (APR). Results and conclusions: Statistical analysis using t-test for paired samples revealed a decrease in mean nasal resistance, with AAR showing a difference of 0.19 Pa/s/cm3 and APR reduced by 0.24 at 75 Pa and 0.20Pa/s/cm3 at 150 Pa. furthermore, the Kruskal-Wallis H-test did not demonstrate a statistically significant reduction in nasal resistance, indicating that the decrease occurs independently of the type of surgical procedure performed. This study confirms respiratory benefits following mono and bi-maxillary orthognathic surgery and highlights the importance of achieving skeletal harmony alongside preservation of oropharyngeal function.