Gender-based Comparison of Pharyngeal Airway Between Class I and Class III Patients During MP3cap Growth Period.

Objective: To compare the pharyngeal airway size and area between Class III patients exhibiting optimal vertical growth direction and Class I patients at the MP3cap stage, considering gender differences.

Methods: This retrospective study analyzed pre-treatment cephalograms of a total of 180 patients with Class I (45 girls, 45 boys) and Class III (maxilla or maxillo-mandibular origin) (45 girls, 45 boys) malocclusions. Linear and angular measurements were conducted on lateral cephalograms utilizing the GNU Image Manipulation Program (GIMP 2.10.18, NY, USA; https://www.gimp.org/). The pharyngeal airway areas were computed utilizing AUTOCAD (Autodesk 2018, San Rafael, CA, USA). The Independent Samples t-test and Mann-Whitney U test were employed for comparative analysis of variables across groups. The forward selection method was employed in conjunction with regression analysis.

Results: No significant differences were observed in the nasopharyngeal area (NA; mm²) across the malocclusion groups and genders. In Class III girls, the oropharyngeal area (OA; mm²), retroglossal (RG; mm²) area, and superior pharyngeal space (SPS; mm) were significantly larger than those of Class III boys, and Class I girls (p<0.05). The inferior pharyngeal space (IPS; mm) was significantly larger in Class III girls compared to Class III boys (p<0.05). Girls with Class I/III malocclusions demonstrated a more pronounced head posture than boys (p<0.05).

Conclusion: The findings indicate the necessity of accounting for gender-specific variations in Class I and III patients, as well as evaluating pharyngeal airway characteristics in orthodontic diagnosis and treatment planning. In Class III girls, the OA and RG areas, as well as the superior and inferior pharyngeal spaces, were larger compared to Class III boys.