Study On The Relationship Between Upper Airway Morphology And Craniofacial Morphology In Young Adults

Objectives:To observe the correlation between craniofacial morphology and upper airway size and the morphological characteristics of upper airway.Materials and Methods:A total of 200 patients aged 18-20 years who were admitted to our hospital for the first time and underwent CBCT from September 2017 to February 2021 were selected from the image database of Stomatological Hospital of Shandong University.Dolphin 11.8 software was used to measure skeletal indexes and upper airway size and shape indexes with SPSS 25.0 Statistical analysis was performed by software,and descriptive statistics were made on skeletal index and upper airway index(volume,transverse diameter,anteroposterior diameter,cross-section diameter ratio,cross-sectional area),and the gender difference of each measurement was analyzed by independent sample T test.One-way ANOVA was used to compare the difference of the difference of transverse diameter,anteroposterior diameter,cross-sectional diameter ratio and crosssectional area of upper airway in different cross sections to analyze the morphological characteristics of upper airway.Pearson correlation analysis was used to explore the correlation between craniofacial skeletal pattern and upper airway volume,and multiple stepwise regression analysis was conducted to analyze the impact of craniofacial skeletal pattern on upper airway size.Results:1.Gender differences of upper airway:total upper airway volume,glossopharyngeal volume,laryngopharyngeal volume,anteroposterior diameter of soft palate apex section,transverse diameter and anteroposterior diameter of epiglottis top section,transverse diameter and anteroposterior diameter of epiglottis bottom section,minimum upper airway cross-sectional area were all larger in males than in females,but transverse diameter of posterior nasal ridge section was smaller in males than in females.The volume of upper airway nasopharynx and palatopharynx had no significant difference among different genders.There was no significant difference in anteroposterior diameter of posterior nasal spine plane and transverse diameter of soft palate apex plane between genders.In terms of upper airway morphology,the airways in each horizontal section were irregular oval with large transverse diameter and small anteroposterior diameter.The airways in the plane of posterior nasal ridge were closest to round,and the lower the section,the more oval the airways were.In different genders,except for the bottom plane of epiglottis,there were gender differences in diameter ratios of other planes.The ratio of male to is smaller than that of female,that is,the cross-section shape of female airway is wider and flatted.2.Upper airway morphology analysis:there were statistical differences in transverse diameter,anteroposterior diameter,cross-sectional diameter ratio and crosssectional area between different sections,regardless of male or female.The order of transverse diameters of upper airway sections was bottom of epiglottis>top of epiglottis>posterior nasal spine>tip of soft palate,but there was no significant difference in transverse diameters of female upper airway except posterior nasal spine and top of epiglottis.The anteroposterior diameter of posterior nasal spine section was significantly larger than that of the other three sections,but there was no significant difference in the anteroposterior diameter of the other three sections.The lower the upper airway is,the greater the ratio of transverse diameter to anteroposterior diameter,that is,the flatter the airway cross-section is,but there is no significant difference between the top and bottom planes of epiglottis.The transverse area of male posterior nasal ridge was the largest,followed by the bottom and top of epiglottis,and the tip of soft palate was the smallest.There was no significant difference between the top and bottom of epiglottis.There were significant differences between the posterior nasal spine section and other sections in female.There was significant difference between the section of apex of soft palate and the section of bottom of epiglottis,but there was no significant difference between the section of bottom of epiglottis and the section of apex of soft palate.3.The correlation and regression analysis between craniofacial skeletal pattern and upper airway volume:The total upper airway volume was correlated with maxillary width,horizontal position of hyoid bone and mandibular length in females(R2=20.8%),but there was no correlation between the total upper airway volume and craniofacial morphology in males.Female nasopharyngeal volume was correlated with anterior height(R2=15.7%),but no correlation was found between male nasopharyngeal volume and craniofacial morphology.Velopharyngeal volume was correlated with maxillary width in females(R2=1.15.1%)and anterior height in males(R2=6.0%).The female tongue pharyngeal volume was correlated with the vertical height of mandibular Angle and hyoid bone(R2=9.6%),but the male tongue pharyngeal volume was not correlated with craniofacial morphology.Laryngeal volume was correlated with the horizontal position of hyoid bone in females(R2=13.9%),and with the horizontal position of hyoid bone and maxillary width in males(R2=13.3%).The minimum upper airway crosssectional area was correlated with mandibular length in males(R2=4.3%),but no correlation was found between the minimum upper airway cross-sectional area and craniofacial morphology in females.Conclusions:1.There were significant differences in upper airway between different genders.The upper airway volume,line distance and cross-sectional area in males were larger than those in females,and the cross-sectional shape of females was flatter.The upper airway has large lateral diameter and small anteroposterior diameter.The lower the upper airway was,the more elliptical it was.The results showed that the upper airway nasopharyngeal segment had the largest cross-sectional size and the palatopharyngeal segment had the smallest cross-sectional size.2.The influence of craniofacial morphology on upper airway was complex and multivariate.Craniofacial morphology has a certain influence on upper airway size,but its weight was small.There were differences in the indices of craniofacial skeletal pattern affecting upper airway size between genders,and the influence of craniofacial skeletal pattern on upper airway size was greater in females than in males.The influence of maxillary width on the palatopharyngeal volume and the correlation between the anterior and posterior position of hyoid bone and laryngeal volume were obvious.