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Objective: To study the difference of airway volume among the adolescent subjects with various vertical skeletal patterns. Methods: CBCT records of 88 adolescents with normal sagittal facial pattern were collected and divided into 3 groups according to their FH-MP angle. The subjects of the 3 groups were matched in age and sex. Airway volume and cross-sectional areas were compared among the 3 groups with Dolphin software. Correlation analyses of the airway dimensions with the maxillofacial variables was carried out. Results: There were statistical differences among the 3 groups in volumes of velopharynx,glossopharynx and oropharynx, minimal cross-section area of oropharynx and cross-section area on EP plane,and all the measurements decreased from low angle to normal angle to high angle groups(P ＜ 0. 05). Cross-section areas of HP plane and SP plane in low angle group were significantly larger than that of the normal angle and high angle groups(P ＜ 0. 05). The oropharyngeal airway dimensions showed negative correlation with FMA,and positive correlation with Co-Po,Ar-Gn (except cross-section area of HP). Conclusion: The pharyngeal airway volumes among different vertical skeletal patterns in adolescents are different.
ABSTRACT
Objective @#To compare the depth of the curve of Spee in Angle classⅡ malocclusion patients with different vertical skeletal patterns and to investigate the relationship between the depth of the curve of Spee and dentofacial morphology. @*Methods @#101 Angle classⅡ malocclusion patients were selected and randomly divided into 3 groups based on their GoGn-SN angles-high angle, average angle and low angle. Lateral cephalograms and dental models of all patients were evaluated to analyze Spee curve depth difference among different groups, Correlation analysis and a multiple linear regression analysis were performed to determine the relationship between the depth of the curve of Spee and all selected cephalometric variables.@*Results@# There was statistical difference in depth of the curve of Spee among different groups P < 0.05. The depth of the curve of Spee was least in the high angle group and greatest in the low angle group. GoGn-SN angle had statistically significant negative correlation with the depth of the curve of Spee, r = 0.428, P = 0.000, ODI, S-Go/N-Me、L7-GoGn angle had statistically significant positive correlation with the depth of the curve of Spee, r = 0.381, 0.357, 0.333, P = 0.000, 0.000, 0.001. The multiple linear regression analysis with stepwise method showed GoGn-SN angle had significant contribution to the depth of the curve of Spee. In Angle classⅡ malocclusion patients, there was statistical difference in depth of the curve of Spee among different vertical skeletal patterns@*Conclusion @#The depth of the curve of Spee is correlated with dentofacial morphology, GoGn-SN angle had significant contribution to the depth of the curve of Spee, which should be taken into consideration during orthodontic diagnosis and treatment.
ABSTRACT
Objective:To study the morphological characteristics of temporo-mandibular joint with high angle vertical skeletal pattern in adult females with class II skeletal type.Methods:41 CBCT films of adult females (20 normal controls;21 skeletal class II high angle subjects)were collected.The position of and form of condyle,form of fossa and joint spaces were measured by Mimics 17.0 soft-ware.Results:Compared with the control group the condyles in high angle patients located more posterior.The joint fossae were lower. The angles of posterior joint node bevels were smaller.The condyles were shorter,thinner and tipped more anteriorly.The position of the conyles were more anteriorly.Conclusion:Class II skeletal type adult females with high vertical skeletal patterns have different forms of fossae,different positions and forms of condyle compared with the normal controls.