The structural change in the hyoid bone and upper airway after orthognathic surgery for skeletal class III anterior open bite patients using 3-dimensional computed tomography.
10.4041/kjod.2009.39.2.72
- Author:
Yoon Seob LEE
1
;
Hyoung Seon BAIK
;
Kee Joon LEE
;
Hyung Seog YU
Author Information
1. Department of Orthodontics, College of Dentistry, Yonsei University, Korea.
- Publication Type:Original Article
- Keywords:
Three-dimensional computed tomography (3D CT);
Skeletal class III openbite;
Hyoid bone;
Upper airway
- MeSH:
Humans;
Hyoid Bone;
Mandible;
Open Bite;
Orthognathic Surgery;
Osteotomy;
Skull
- From:Korean Journal of Orthodontics
2009;39(2):72-82
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
OBJECTIVE: The purpose of this study was to investigate the structural changes of the hyoid bone and upper airway after orthognathic surgery for skeletal class III anterior open bite patients, and make comparisons with normal occlusion. METHODS: Pre- and post-operative computed tomography (CT) examinations were performed on 12 skeletal class III anterior open bite patients who were treated with mandibular setback osteotomy. Using the V-works 4.0(TM) program, 3-dimensional images of the total skull, mandible, hyoid bone, and upper airway were evaluated. RESULTS: In the Class III openbite group, the hyoid bone were all positioned anteriorly, compared to the Normal group (p < 0.05). The angle between the hyoid plane and mandibular plane in the Class III openbite group before surgery was greater than in the Normal group (p < 0.05), and the difference increased after surgery (p < 0.01). In the Class III openbite group, the volume of the upper airway decreased after surgery (p < 0.001) and the volume of the upper airway was smaller than the Normal group before and after surgery (p < 0.001). CONCLUSIONS: The narrow upper airway space in skeletal Class III openbite patients decreased after mandibular setback osteotomy. This may affect the post-surgical stability.
