Evaluation Of Upper Airway In Adult Skeletal Class â…  Patients With Different Vertical Patterns Based On Cone-beam Computed Tomography Images

As the main passageway of exchanging air, the upper airway’s main functions such asswallowing, respiration,pronunciation have closely relationship with growth anddevelopment of craniomaxillofacial.As a kind developmental deformity ofcraniomaxillofacial, malocclusion prevalence of the children and adolescents in China isfrom51.84to72.97%,in which malocclusion Class Ι is higher than50%.For thisreason,there are many studies on the relationship between morphology and function of theupper airway with malocclusional pattern,but rarelry on the upper airway morphologiccharacteristics in the same sagittal skeletal Class patients with vertical dysplasia.Most ofprevious investigations about the airway morphologic characteristics were based on lateralcephalometric analysis which only provide2-dimensional images,but there are certainlimitations to present overall complicated three-dimensional structure of the upper airway.In order to provide reference to the growth and development of craniomaxillofacial and treatment plan in clinical,this study based on cone-beam computedtomography(CBCT) aimed to do a3-dimensional evaluation on the upper airwaydimensions of skeletal Class I adult patients with different vertical patterns，to observewhether there are differences,and further to discuss the relationship with the growth anddevelopment of craniomaxillofacial.Objective：CBCT was carried on in skeletal Class I patients with different vertical patterns, thensofeware Mimics10.01was used to built nasopharynx，oropharynx3-dimensionalimages,and to measure and compare the differences of nasopharynx, palatopharynx andglossopharynx,so as to discuss the relationship between different morphologic of theairway with craniomaxillofacial.Methods1．According to the inclusion and exclusion criteria,60skeletal Class I patients (30women，30men，average age：28.6) were involved in this study,in which high-angle20,average angle20,low-angle20per group.2．The3D CBCT images of nasopharynx and oropharynx for volumetric analysis werebuilt by Mimics10.01．3．T-test was carried on for the comparisons of the differences between different gender ofthe same vertical skeletal pattern; single factor analysis of variance was performedamong the different vertical skeletal pattern groups with the same gender; Pearson’scorrelation coefficient was performed for the association between the airwaymeasurement data and ANB Angle or GoGn-SN Angle.Statistical tests wereperformed by SPSS19.0.Result1．The differences of the upper airway in different genders with the same vertical skeletalpatternMost line distance of the men’s airway is much longer than women’s in the samevertical skeletal pattern, but there were no statistical significance (P>0.05) except ETP– L;all the cross sectional area and volume of the men’s airway are larger than women’s inthe same vertical skeletal pattern.2．The differences of the upper airway in different vertical skeletal patternThere were no statistical significance (P>0.05) except ETP–L in line distance ofdifferent vertical skeletal pattern; low angle group is largest and high angle group issmallest in cross sectional area and volume of the airway with different vertical skeletalpattern, but there were no statistical significance (P>0.05) except UTP-S, ETP-S, PP-V, GP-V, V total.3．The correlation analysis betewen the airway of different skeletal pattern and ANBAngle or GoGn-SN AngleThe data having statistical significance of the upper airway in skeletal Class I adultpatients with different skeletal type exsit some degrees of correlation with GoGn-SNAngle,and no correlation with ANB Angle.ConclusionIn skeletal Class I adults with different vertical patterns,there are statisticaldifferences in palatopharynx and oropharynx airway,which might due to different verticalgrowth type. The lower part of the upper airway in high angle group is more smaller,whichindicates that orthodontists should ask the patients about their status of respiratory systemwhen making the treatment plan in order to prevent further increase thecounter-clockwise trend of the patient’s mandible, and so as to avoid iatrogenicobstructive sleep apnea syndrome(OSAS).