CBCT Measurement And Analysis Of Mandibular And Oropharyngeal Airway Morphology In Adolescent Female Skeletal Class Ⅱ Malocclusion

Objective CBCT measurement was used to analyze the relationship between the morphology of mandible and oropharyngeal airway in adolescent female patients with skeletal Class II mean angle type malocclusion,and then to explore the effect of mandible morphology on oropharyngeal airway,so as to provide clinical reference for the diagnosis and treatment of adolescent female patients with skeletal Class II mean angle type malocclusion.Methods According to the inclusion criteria,40 adolescent female patients with skeletal Class II mean angle type were selected.According to the Quantitative Cervical Vertebral Maturation,they were divided into two groups: early adolescence group(bone age stage of cervical spine is I and II,with an average age of11.07 ± 0.76 years)and late adolescence group(bone age stage of cervical spine is III and IV,with an average age of 14.33 ± 1.22 years).All study subjects took CBCT images before treatment and imported the obtained image data into the three-dimensional image processing software invivo 5.0 for measurement,The measurement items include: ∠SNA,∠SNB,∠ANB,oropharyngeal airway volume V,height H,minimum cross-sectional area Smin,minimum cross-sectional sagittal diameter Ymin,cross-sectional diameter Xmin,mandibular body width L1 and length(L2,L3).Using statistical software spss22.0 system makes statistical analysis on the above measurement items,compares the mean value of the above measurement indicators,and judges whether there are differences.All data conform to the normal distribution,The bivariate with equal square difference adopts two independent sample t-test,and the measurement data of mandible and oropharyngeal airway morphology adopts Pearson correlation analysis method.Results 1.The mandibular measurement parameters,oropharyngeal airway volume,height and minimum cross-sectional area in the late adolescence group were significantly higher than those in the early adolescence group(P<0.05);2.There was no significant correlation between oropharyngeal airway measurement indexes and∠SNA,∠SNB,∠ANB in the two groups(P>0.05);3.There was a positive correlation between the length of mandible and the volume of oropharyngeal airway(P<0.05);4.There was a positive correlation between mandibular width and oropharyngeal airway volume and minimum cross-sectional area in the two groups(P<0.05);5.There was a positive correlation between mandibular body length and mandibular total length and the minimum cross-sectional area of oropharyngeal airway in late adolescence group(P<0.05).Conclusions 1.In adolescence,the shape of oropharyngeal airway increases with age;2.There is a certain correlation between oropharyngeal airway and mandibular morphology in adolescent female patients with skeletal Class II malocclusion,that is,the volume of oropharyngeal airway increases with the increase of mandibular length and width.