Does tongue volume correlate with the upper airway and craniofacial structure of the skeletal Class III malocclusion pattern? A cross-sectional descriptive study in Vietnamese children

Background : This study aims to assess the impact of TV on craniofacial and maxillary airway morphology in Vietnamese children with skeletal Class III malocclusion using cone beam computed tomography (CBCT). Methods : A cross-sectional descriptive analysis was conducted on a total of 90 children (14–18 years old, 29 males and 61 females) from July 2023 to July 2024 with skeletal Class III malocclusion (angle formed by the A-nasion line and B-nasion line (ANB) ≤ 0, Wits appraisal ≤ 2), a body mass index of 18–25 kg/m 2 , no history of orthodontic treatment or orthognathic surgery, and no history of cleft lip or palate treatment. Lateral cephalometric radiography and CBCT were performed for each participant to identify differences and analyze the correlation of airway dimensions and craniofacial structure with TV. Results : The study revealed significant gender variations in molar dimension, age, and craniofacial measures. Males had higher TV, OCV, and pharyngeal airway volume than females, but the TV/OCV ratio was not significant. Age raised most metrics, with TV, OCAV, and OCV positively correlated. Tongue volume may affect airway dimension, since TV demonstrated a significant positive correlation with different parts of. Some craniofacial measurements were significantly associated with TV, particularly those related to the line between ANS and PNS present for Palatal plane (ANS-PNS) and L7-7.Other measurements, such dental width, did not correlate with TV. Conclusions : The study found significant differences in TV and dental arch width among individuals with skeletal Class III malocclusion, a negative correlation between TV and interincisal angle, and a significant negative correlation between the TV/OCV ratio and pharyngeal and oral airway volumes, indicating that TV, OCV, and their ratio are important for preserving airway patency and early recognition of upper airway abnormalities.