关键词: 骨性Ⅱ类, 垂直骨面型, 上气道, 颞下颌关节

Abstract:

Objective To investigate the correlation between three-dimensional upper airway morphology and temporomandibular joint (TMJ) structural characteristics in skeletal Class Ⅱ malocclusion patients with different vertical skeletal patterns. Methods Thirty-six adult patients with skeletal Class Ⅱ malocclusion who attended the Department of Orthodontics at our hospital between January 2021 and December 2024 were enrolled and divided into hypodivergent, normodivergent and hyperdivergent groups according to vertical skeletal pattern. All patients underwent CBCT examination. Three-dimensional airway reconstruction was performed using Dolphin Imaging 11.9 software. The volumes of the nasopharynx,velopharynx,glossopharynx, laryngopharynx as well as the minimum cross-sectional area of the oropharynx were measured. TMJ measurements included mediolateral condylar diameter, anteroposterior condylar diameter, condylar length, glenoid fossa width, glenoid fossa height and the sagittal position of the condyle within the fossa. The anterior and posterior joint spaces were recorded, and a linear ratio (LR) was calculated. One-way ANOVA was performed using SPSS 26.0 to compare intergroup differences; Pearson correlation analysis was used to evaluate the relationship between upper airway dimensions and TMJ structural parameters. Results Significant differences were found among the three groups in nasopharyngeal, velopharyngeal and glossopharyngeal airway volumes, as well as in the minimum cross-sectional area of the oropharynx (P<0.05). A decreasing trend from the hypodivergent group to the hyperdivergent group was observed. Significant intergroup differences were also found in anteroposterior condylar diameter and condylar length (P< 0.05). Correlation analysis showed that airway volumes were negatively correlated with the LR in both the hypodivergent and hyperdivergent groups. Conclusion CBCT-based findings indicate a correlation between TMJ morphological characteristics—particularly condylar position—and upper airway structure. Evaluation of condylar position should therefore be considered when assessing the airway during orthodontic treatment planning for patients with skeletal Class Ⅱ malocclusion.

Key words: skeletal Class Ⅱ, vertical facial type, upper airway, temporomandibular joint