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

Upper airway is surrounded by the bone and soft tissue of the craniofacial. More andmore researches pay attention to the relationship between the upper airway and themorphology and structure of craniofacial. Previous studies about the relationship betweenupper airway and craniofacial were based on X-ray analysis that were mainly focused onthe sagittal pattern. Cone-beam computed tomography (CBCT) is increasingly beingapplied to the oral clinical with the development of three-dimensional images, it is a newmethod to study the relationship between the upper airway and craniofacial.Skeletal Class Ⅲ malocclusion, a common malocclusion in the clinical, is seriouslyinfluenced on oral function and facial appearance of the patients. There are differentcharacteristics of craniofacial in the different vertical facial types. Now there were fewreports in there-dimensional direction and it is still unclear for the relationship between theupper airway and craniofacial.Objective:In order to study the characteristics and differences of upper airway in adult skeletalclass III with different vertical facial types, the research has measured the there- dimensional direction data by CBCT. The purpose of this study was to investigate therelationship between the upper airway and craniofacial characteristic.Methods:This study selected Sixty-two adult（33female,29male）skeletal class III patients,who received orthodontic treatment in Department of Orthodontics, college of Stomatology,Fourth Military Medical University from2010to2012. All of them were divided into threegroups based on their GoGn-SN angles: high-angle group, average angle group andlow-angle group respectively. Three dimensional airway volumes、lengths and widthswere measured by Mimics. Cross-sectional areas was measured by autoCAD.All the datawere analyzed by the means of SPSS17.0. The statistical methods in this study wereindependent sample t-test in the male and formale,Single-factor analysis of variance andPairwise comparisons in different vertical facial types, Pearson correlation analysis on theANB GoGn-SN, FMA, ODI, APDI and the airway data.Results:1.The upper airway measurement data had significant differences in the UTH, UTS,ETV between male and female(P<0.01). The rest of measurement data didn’t havesignificant differences（P>0.05）.It showed that the male measured data were less than thefemale in the nasopharynx, but they were greater than the female palate pharynx andoropharynx by the Variance analysis.2.There were significant differences in the PNSL、PNSS、UTS、UTV、ETV and Vof the male upper airway, The pairwise analysis showed that high-angle group of male isless than the average angle group and the low-angle group on the PNSS, UTS, ETV.Therewere obvious differences in the UTL and EPS in female（P<0.05）. The rest of themeasurement data were not significant.3.There was no statistically significant on the ratio of sagittal diameter and coronaldiameter. But it showed that measured value in the high-angle group was less than theaverage angle group and the low-angle group.4. There was statistically significant on the ANB and UTS、ETS;GoGn-SN and UTL、UTS、UTV、ETL、ETV；FMA and UTH、ETV；ODI and PNSV、UTS、UTV、ETL、ETS、ETV、V. But the correlation coefficient are from0.2to0.3. But the rest of measurement data didn’t have significant differences.Conclusion:The differences of the upper airway in UTH、UTS、ETV between male and femalewere significant. The differences in PNSL、PNSS、UTS、UTV、ETV of male and in UTLand ETS of female were significant in adult skeletal class III with different vertical facialtypes. And the date of high-angle group are less than the average angle group and thelow-angle group on the PNSS, UTS, ETV in the male. In the correlation analysis there isa relationship between the upper airway form in adult skeletal class Ⅲ malocclusion andthe vertical facial types.We also need to further analyze the soft tissue around the airway,because the morphology of the airway also requires a comprehensive analysis of thecraniofacial and the soft tissue.