Cone-beam Computed Tomography Evaluation of Upper Airway Morphology and its Association with Age, Gender, and Body Mass Index in Healthy Adults

This cross-sectional study used Cone-Beam Computed Tomography (CBCT) to evaluate the association between the Upper Airway (UA) volume and demographic risk factors, including age, gender, and Body Mass Index (BMI), in healthy Indonesian adults.

A retrospective cross-sectional study was conducted on 85 CBCT datasets (45 males, 40 females; ages 20-40 years). Upper airway segmentation was performed using CS 3D Imaging Software to obtain the measurement parameters, such as total UA volume, minimal cross-sectional area (CSAmin), and lateral and anteroposterior CSAmin dimensions. Inter- and intra-rater reliability were assessed using Intraclass Correlation Coefficients (ICC). Correlation analyses (Spearman’s Rho) and group comparisons were used to evaluate associations between airway parameters and age, gender, and Body Mass Index (BMI).

A reliability test for the upper airway measurement parameters was conducted by two examiners over a two-week interval, and the findings indicated that inter-rater reliability was excellent (ICC=0.99), and intra-rater reliability was good (ICC=0.80-0.89). The total UA volume differed significantly by gender (males: 31.7 ± 7.0 cm³; females: 27.1 ± 5.0 cm³; p < 0.05), age group (p < 0.05), and BMI category (p < 0.05). Weak negative correlations were observed between total UA volume and both gender (r = –0.327, p < 0.05) and BMI (r = –0.326, p < 0.05), while age showed no significant correlation. CSAmin and linear dimensions showed no significant correlation with any demographic variable, and all CSAmin values exceeded 110 mm².

In this study, upper airway volume was significantly greater in males than in females, consistent with previous findings. Participants with normal BMI exhibited the highest airway volumes, while overweight individuals showed reduced volumes. On the other hand, age did not correlate significantly with upper airway parameters in this 20- 40-year-old cohort.

Upper airway volume is significantly associated with gender and BMI, but not with age, in healthy adults aged 20-40 years. Three-dimensional CBCT provides reliable measurements for UA assessment and may support early identification of airway alterations in clinical practice.