An analysis of upper airway and hyoid bone on cone-beam computed tomography in female adolescents with different vertical facial types

HAN Bei-lei; DENG Hai-yan; YANG Li; LIU Hai-xia; MENG Qing-fang

doi:10.3969/j.issn.1001-9448.2017.07.012

Abstract：Objective To investigate the difference of the upper airway dimensions and hyoid bone position in female adolescents with different vertical facial types.Methods Thirty-nine female adolescent patients aged 10-15 years old with Skeletal Class Ⅰ but in different vertical facial types were selected.Cone-beam computed tomography (CBCT) image was performed in the first visit for dental treatment.According to the measuring average of Chinese normal occlusion by Steiner analysis method,all the subjects were divided into 3 groups,low angle group (GoGn-SN ＜ =27.3 °),normal angle group (27.3 ° ＜ GoGn-SN ＜ 37.7 °) and high angle group (GoGn-SN ＞ =37.7 °) according to GoGn-SN angle.The images were subsequently imported into materialism's interactive medical image control system (MIMICS) (v.16.0,materialise) to accomplish the reconstruction of upper airway,measuring and analyzing the upper airway dimensions and the hyoid bone position.Results Among the 3 groups,there were significant differences in AP,AP2 and R2 (P ＜0.05),except for in length,cross-sectional area or volumes (P ＞ 0.05).The AP2 in normal angle group was significantly lower than low angle group;the AP1 and AP2 in high angle group were significantly lower than low angle group,while the R2 was per contra (P ＜ 0.01,P ＜ 0.05).There were significant differences in hyoid bone position in C3-Me,H-X and H-S-Ba among the 3 groups (P ＜ 0.05),which were significantly lower in high angle group than low angle group (P ＜ 0.01).Conclusion There are differences in the upper airway dimensions and hyoid bone position in female adolescence with different vertical facial types.