title: Effects of Le Fort I Osteotomy on the Nasopharyngeal Airway-6-Month Follow-Up.
abstract: OBJECTIVE
  The literature discussing the impact of a single Le Fort I osteotomy on nasopharyngeal airways is limited. This study assessed the volumetric changes in the nasopharyngeal airway after a single Le Fort I osteotomy and explored the correlation between these changes and 3-dimensional surgical movements of the upper jaw.
  
  
  METHODS
  This retrospective study was conducted in 40 patients who had undergone a single Le Fort I (maxillary advancement with or without impaction) to correct Class III malocclusion with maxillary hypoplasia. Preoperative (T1) and 6-month postoperative (T2) cone-beam computed tomographic (CBCT) scans of these patients were used for analysis. Maxillary surgical movements and volumetric changes in the nasopharyngeal airway were measured. The reproducibility of the measurements was evaluated using paired t tests and intraclass correlation coefficients. The Wilcoxon test and Pearson correlation coefficient were applied to evaluate the volumetric changes in the nasopharyngeal airway space and assess the correlations of these changes to the maxillary surgical movements.
  
  
  RESULTS
  Six patients were excluded from the study owing to major differences (>5°) in their head and neck posture between the T1 and T2 CBCT scans. The errors of the repeated measurements were insignificant (P > .05), with a high level of agreement (r = 0.99; P < .05) between the repeated digitization of the landmarks. There was a statistically significant impact of a Le Fort I osteotomy on the right maxillary sinus (decreased by 17.8%) and the lower retropalatal space (expanded by 17.3%; P < .05). The correlation between the change in airway volume and the magnitude of surgical maxillary movements was moderate (r = .4). Similarly, there was a moderate correlation between changes in the upper nasopharynx and those in the hypopharynx.
  
  
  CONCLUSIONS
  The single Le Fort I osteotomy was found to increase the retroglossal airway volume. This could be important for the treatment of obstructive sleep apnea in patients with maxillary deficiency. A long-term follow-up assessment of a larger sample with a functional assessment of airway would be beneficial to confirm these findings.
authors.affiliation: Honorary Specialist Registrar, Glasgow University, MVLS College, Glasgow Dental Hospital & School, Glasgow, UK. Electronic address: dr_muzian@hotmail.com.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Almuzian
authors.affiliation: Postgraduate Student, Glasgow University, MVLS College, Glasgow Dental Hospital & School, Glasgow, UK.
authors.forename: Anas
authors.initials: A
authors.lastname: Almukhtar
authors.affiliation: Medical Devices Unit, NHS Greater Glasgow and Clyde, Glasgow, UK.
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Ju
authors.affiliation: Postgraduate Student, Glasgow University, MVLS College, Glasgow Dental Hospital & School, Glasgow, UK.
authors.forename: Ali
authors.initials: A
authors.lastname: Al-Hiyali
authors.affiliation: Consultant Orthodontist, Glasgow Dental Hospital & School, Glasgow, UK.
authors.forename: Philip
authors.initials: P
authors.lastname: Benington
authors.affiliation: Professor, Department of Oral and Maxillofacial Surgery, Glasgow University, MVLS College, Glasgow Dental Hospital & School, Glasgow, UK.
authors.forename: Ashraf
authors.initials: A
authors.lastname: Ayoub
mesh_terms: D000293:Adolescent; D000328:Adult; D059925:Anatomic Landmarks / Q000000981:diagnostic imaging; D002508:Cephalometry / Q000379:methods; D054893:Cone-Beam Computed Tomography / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007013:Hypopharynx / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D008313:Malocclusion, Angle Class III / Q000601:surgery; D008437:Maxilla / Q000002:abnormalities; D063166:Maxillary Osteotomy / Q000379:methods*; D008443:Maxillary Sinus / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D008875:Middle Aged; D009305:Nasopharynx / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D009929:Organ Size; D019340:Osteotomy, Le Fort / Q000379:methods*; D010159:Palate / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D015203:Reproducibility of Results; D012189:Retrospective Studies; D055815:Young Adult