Sanaz Soheilifar; Mohammad Ali Momeni
Abstract
Background: According to the close proximity of hyoid bone with dentofacial structures and its muscular attachments, a probable relationship between it and different types of skeletal patterns is suspected.
Objectives: The aim of this study is compare the position of hyoid bone in skeletal class I and ...
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Background: According to the close proximity of hyoid bone with dentofacial structures and its muscular attachments, a probable relationship between it and different types of skeletal patterns is suspected.
Objectives: The aim of this study is compare the position of hyoid bone in skeletal class I and class II patients.
Methods: In this study 50 cephalograms were divided into two groups, skeletal class I (1 ≤ ANB ≤ 4) and skeletal class II (ANB > 4), with 24 and 26 patients in each group, respectively. Horizontal and vertical position of hyoid bone were evaluated. SPSS software and student t-test were used to analyze the data. Results: According to the results of our study, there is no statistically significant difference between the hyoid bone position in skeletal class I and skeletal class II patients.
Conclusions: Since the hyoid bone position is similar in skeletal class I and class II patients, the skeletal pattern is not the only determinant of the position of hyoid bone.
Koroush Taheri Talesh; Javad Yazdani; Amir Mohammadi; Azin Sohrabi; Aydin Sohrabi
Abstract
Introduction: It has been advocated that treatment of dentofacial deformities with jaw osieotomies may influence upper airway morphology, and several studies has shown that mandibular setback surgery has the potential to diminish airway size and alter the hyoid bone position.Objective: The purpose of ...
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Introduction: It has been advocated that treatment of dentofacial deformities with jaw osieotomies may influence upper airway morphology, and several studies has shown that mandibular setback surgery has the potential to diminish airway size and alter the hyoid bone position.Objective: The purpose of this study was to evaluate the effect of mandibular setback on the pharyngeal airway size, and hyoid bone position and to evaluate if a pre-surgical prediction on PAS can be made or not.Materials and methods: Twenty eight pre- and post-operative (3-4 months) lateral cephalograms of 28 individuals (16 females and 12 males older than 17) who had undergone vertical ramus ostetomy setback surgery to correct skeletal class III discrepancies. Cephalograms were traced and a paired-sample t-test was used to evaluate the difference between 11 linear variables pre- and post-operative measurements. Coefficient correlation was calculated for the amounts of setback and the change in airway size.Results: The vertical and horizontal position of hyoid and hyoid-mandible distance do not change significantly. Hyoid-2nd cervical vertebra and hyoid-pogonion distances reduced significantly. In the case of upper airway indicators, the width of pharynx was calculated at 4 different levels. In all 4 levels, statistical analysis revealed significant reduction but the correlation of reduction in the size of pharynx versus amount of setback is not significant (respectively from the most superior width to the most inferior one r=0.15, r=0.13, r=0.09, r=0.19).Conclusion: This study suggested that mandibular setback surgery can decrease the pharyngeal airway size.
