골격성 Ⅲ급부정교합자와 I급정상교합자들에서 설골위치에 따른 기도크기와 하악위치의 비교 평가

PHARYNGEAL AIRWAY WIDTH AND MANDIBULAR POSIT10N RELATIVE OT HYOID BONE POSIT10N IN CLASS I NORMAL OCCLUSION AND CLASS ⅢMALOCCLUSION

Various studies have documented a variability of hyoid bone position in relation to changed mandibular position or head posture. The aim of this study was to evaluate the hyoid bone position and inclination on the lateral cephalometric radiographs of two group of patients exhibiting Class Ⅰ normal occlusion and Class Ⅲ malocclusion , so to verify the relationships between hyoid bone position, pharyngeal airway and relative mandibular position In the Class Ⅰ group, there were 16 males and 14 females, while the Class Ⅲ group consisted of 19 males and 11 females. The results were as follows 1. By the length of A-APH, N-APH, S-APH, and GoP-PPH, PPH-FH, the hyoid bone of Class Ⅲ group was more anteriorly and inferiorly positioned than Class Ⅰ group 2. On the analysis of soft tissue airway, the measurements(PNS-ad) of Class Ⅲ group were more smaller than Class Ⅰ group 3. In the comparison of the variances between male and female, hyoid bone was more inferiorly positioned and showed significantly more larger pharyngeral width of hard tissue in the Class Ⅰ male and in the Class Ⅲ male, same tendancy about hyoid position and pharyngeal width was seen and more anteriorly positioned. 4. There was no statistically significances between pharyngeal airway measurements and relative mandibular position, but statistical significance between wits appraisal and hyoid bone position was seen. 5. The S-N-Pog which shows relative mandibular protrusion showed inverse ratio in the analysis with A-APH, N-APH and Facial ratio with LAH-Mp also showed inverse ratio.