Objective <p>This study aims to systematically analyze the impact of adenoid hypertrophy on dental, maxillofacial and airway structures and clarify its pathological mechanisms. Additionally, it seeks to develop a multi-indicator-based diagnostic model to provide a scientific basis for early diagnosis and treatment.</p> Methods <p>A total of 126 subjects were included and divided into three groups according to the A/N ratio (Group A/N ≤ 0.6, Physiological group 0.61 ≤ A/N ≤ 0.7, Pathological group A/N ≥ 0.71).The study compared the mandibular, two—dimensional airway and three-dimensional airway indicators among the three groups and combined stratified analysis with correlation analysis to identify the risk factors for adenoid hypertrophy. The effectiveness of the diagnostic model was verified using ROC curves, calibration curves and DCA decision curves.</p> Results <p>1.There were no significant differences in gender distribution among the three groups (<i>p</i> = 0.404). However, the ANB angle (5.18 ± 2.06 vs.3.73 ± 3.09, <i>p</i> = 0.041) and Z-angle (63 ± 10 vs.57 ± 10, <i>p</i> = 0.014) were significantly higher in the pathological group. This suggests that adenoid hypertrophy may lead to mandibular retrognathia, which in turn may exacerbate Angle Class II malocclusion.2.Three—dimensional airway analysis revealed that the nasopharyngeal volume in the pathological group was 50% less than that in the control group (4,971 ± 1,803 mm³, p &lt; 0.001), confirming its mechanical compressive effect on the upper airway space.3.Age—stratified analysis indicated that in the control group, the U1-SN and U1-NA angles were significantly higher in the ≥ 11 -year- old subgroup (p &lt; 0.05), reflecting physiological compensation. In the physiological group, the U1—SN angle was significantly higher in the 9-to-11-year-old subgroup than in other age groups (<i>p</i> = 0.036), but no difference was found in airway volume. In the pathological group, the Y-axis angle and MP-FH angle were significantly larger in the ≥ 11-year-old subgroup (p &lt; 0.05), implying that early surgical intervention may be necessary for this subgroup.4.A/N was significantly correlated with mandibular, two-dimensional and three-dimensional airway indicators (p &lt; 0.05). Among these, PNS-UPW was identified as an independent risk factor (OR = 0.51, 95% CI = 0.36—0.74, p &lt; 0.001).5.The multi—indicator diagnostic model demonstrated an AUC of 0.950 (95% CI = 0.904–0.982).The calibration curve (Hosmer–Lemeshow test p &gt; 0.05) and DCA decision curve indicated that the model offered significantly higher net benefits than traditional strategies within the threshold probability range of 0.2–0.8.</p> Conclusion <p>This study, leveraging multimodal data analysis, elucidates the pathological process by which adenoid hypertrophy affects dental and maxillofacial development via dual mechanisms of mechanical compression (airway narrowing) and functional compensation (mandibular retrognathia and abnormal tongue position).The developed diagnostic model serves as a quantification tool for the early identification of high—risk children, provides evidence—based support for determining the optimal timing of ENT surgery and designing orthodontic treatment plans, and is anticipated to enhance the precision and timeliness of children's maxillofacial health management.</p>