The Relationship Between Pharyngeal Airway Width and Orthodontic Anomalies

Introduction The relationship between pharyngeal airway and orthodontic anomalies are receiving an increased attention. The respiratory structures are closely related to dentofacial growth and development [1-2]. Therefore, changes in the airway’s width are associated with dentoskeletal malocclusion in the sagittal plane [3]. Aim The aim of this study is to analyze the relationship between pharyngeal airway width and skeletal malocclusion patterns. Methods This retrospective study was approved by the Kaunas Regional Biomedical Research Ethics Committee, number BE-2-100. According to study protocol, 100 patients with a mean age of 18,83±5,36 were randomly selected from the database of the Department of Orthodontics at the Lithuanian University of Health Sciences. Inclusion criteria: pre-orthodontic patients, patients with no congenital syndromes, high-quality lateral cephalograms in natural head position with at least four cervical vertebrae visible. Patients were divided in two groups based on the type of skeletal malocclusion according to ANB (A-point—Nasion—B-point) angle: Angle I (ANB 0-4°) (n = 50), Angle II (ANB >4°) (n = 50). The ANB, upper and lower airway widths were measured in lateral cephalograms using WebCeph software version 2.0.0. The upper airway width was measured from a point on the posterior outline of the soft palate to the closest point on the posterior pharyngeal wall. The lower airway width was measured from the intersection of the posterior border of the tongue and the inferior border of the mandible to the closest point on the posterior pharyngeal wall. The upper airways were considered normal when their width was 17±3 mm, while the lower airways were considered normal at the width of 11±3 mm. Data analysis was done using IBM SPSS version 29.0. Stjudent’s t-test was used, a value of p < 0,05 was stated as significant. Results Out of 100 patients, 61 % (n = 61) were females and 39 % (n = 39) were males. According to ANB angle, 50 % (n = 50) of patients had skeletal Angle I class orthodontic anomaly, while other 50 % (n = 50) had skeletal Angle II class anomaly. The results revealed that the second group of patients with skeletal Angle II class anomaly had significantly narrower upper airways (13,04±3,21 mm) compared to the skeletal Angle I class patients (14,72±2,88 mm) (p = 0,007). Furthermore, the lower airway width was found to be also smaller in patients with skeletal Angle II class anomaly (10.27±2.79 mm) relative to those with skeletal Angle I class anomaly (11.26±2.74 mm), although the results were not statistically significant (p = 0.075). Conclusions In conclusion, the study found significant difference in the upper airway width between patients with skeletal Angle I and Angle II class anomalies, with Angle II patients having narrower upper airways. These findings suggest that the pharyngeal airway width may be associated with different skeletal malocclusions, particularly in the sagittal plane.