No abstract available.
Hyoid Bone ; Orthognathic Surgery ; Recurrence

No abstract available.
Humans ; Hyoid Bone ; Orthognathic Surgery

Carcinoma of the tongue remain one of the greatest management challenges for the head and neck surgeon because of the adverse effects of treatment on oral and pharyngeal function. In early carcinoma of the base of tongue however, the prognosis is encouraging and function of swallowing and speech is preserved despite surgery. Suprahyoid pharyngotomy is one of the surgical approaches advocated for resection of base of tongue tumours with primary anastomosis.
Carcinoma/*surgery ; Hyoid Bone/surgery ; Tongue Neoplasms/*surgery

Humans ; Hyoid Bone ; surgery ; Sleep Apnea, Obstructive ; surgery

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.
Humans ; Hyoid Bone ; Mandible ; Open Bite ; Orthognathic Surgery ; Osteotomy ; Skull

hyoid bone to mandibular plane did not have signifacant difference from Class I group but after operation, it increased more than Class I group significantly. 4. The size of airway reduced after operation. Among this, oropharyngeal airway most reduced.]]>
Chin ; Humans ; Hyoid Bone ; Orthognathic Surgery ; X-Ray Film

surgery changes patient's mandibular position and environment of related anatomic structures. Many clinicians were interested in these changes and studied about this problem. However, most of them were based on two dimensional cephalogram. According to the development of image and computer system, it would be possible that the airway change is analyzed with three dimensional CT. So we tried to measure the volumetric change of airway and analyzed the relationship between the airway structure and volumetric change. Nineteen patients who experienced orthognathic surgery due to mandibular prognathism were analyzed with 3D CT data (preoperative and postoperative 6 months) and 2D lateral cephalometry. Volumetric change was measured and 3 dimensional change of related structure was assessed with simulation program (V-works., 4.0 Cybermed, Korea). Ten patients showed the decrease of airway volume change and nine showed the increase of airway volume change. Volumetric change was determined by dimensional change of mandible and hyoid bone. The dimensional positions of mandible and hyoid bone were the key factor for determining the airway change after surgery. Airway change is also predictable with the dimensional change of mandible and hyoid bone.]]>
Cephalometry ; Computer Systems ; Humans ; Hyoid Bone ; Mandible ; Orthognathic Surgery ; Prognathism

PURPOSE: This study was intended to evaluate the positional relationship between the hyoid bone and the mandible in patients with mandibular protrusion after mandibular set-back surgery by means of 3D-CT. MATERIALS AND METHODS: Preoperative(3 weeks before) and postoperative (6 weeks after) 3D-CT and cephalogram were taken on 32 patients(12 male, 20 female, mean age of 23.2) treated by bilateral sagittal split osteotomy with rigid fixation. The angular measurement on 3D-CT basilar view were deviation of Me and H, long axis angle of left and right cornu majus. The lineal measurement on 3D-CT basilar view were composed of intercondylar line and coordinates(x,y) of Me and H. The angular and lineal measurement of lateral cephalogram were composed of mandibular plane angle, SNA, SNB, ANB, FH-NA and FH-NB, and coordinates(x,y) of B, Pog, Me and H, PAS, Lpw, MPH and IAS. On the frontal cephalogram, deviation of Me were evaluated. RESULTS: The mean mandibular set-back was 8.0mm horizontally and mandibular plane angle was slightly increased. The hyoid bone was displaced postero-inferiorly, the distance between MP(mandibular plane) and H(hyoid bone) was increased and the posterior airway space values (PAS, Lpw, IAS) were decreased. The coordinates Me(x,y), H(x,y) and deviation angle Me' and H'were revealed the strong positive correlation. CONCLUSION: The results revealed that the horizontal, vertical and transverse relationship of the mandibular and the hyoid bone movements were significantly correlated in patients performed mandibular set-back surgery.
Axis, Cervical Vertebra ; Female ; Humans ; Hyoid Bone* ; Male ; Mandible* ; Orthognathic Surgery* ; Osteotomy

surgery influences both the soft and hard tissues in the maxillofacial region, including the tongue and pharyngeal airway. This study was performed to evaluate the changes in the hyoid bone and tongue position, and pharyngeal airway space after mandibular setback osteotomy in 25 patients with mandibular prognathism by means of cephalometric analysis. Lateral cephalograms were obtained at pre-operation(T0) and 2-4days later the operation(T1) and 6 months post-operative follow-up(T2). In this study, we found that there were significant changes in position of hyoid bone and tongue and width of pharyngeal airway space after mandibular setback osteotomy(T1) in persons with mandible prognathism. and except of hyoid bone this change remained stable at 6 months follow up(T2). Especially in analysis with the amount of mandible set back; The cases where the amount of mandible set back was 6~7mm under, there was no significant change in hyoid bone movement. But above 6~7mm there was significant change. The cases where the amount of mandible set back was 11~12mm under, there was no significant change in tongue and pharyngeal airway space width. But above 11~12mm, there was significant change.]]>
Dentition ; Dentofacial Deformities ; Humans ; Hyoid Bone ; Mandible ; Orthognathic Surgery ; Orthognathic Surgical Procedures ; Osteotomy ; Prognathism ; Tongue

surgery in skeletal class III patients, the hyoid bone position and the upper airway dimension could be changed due to mandibular setback. There has been many studies about airway dimension of the patients with skeletal class II malocclusion or obstructive sleep apnea. but not with skeletal class III. The purpose of this study was to examine the change of position of the hyoid bone and the consequent change of airway space as the result of retrusion of mandible after orthognathic surgery in skeletal Cl III malocclusion patients. It is also to apply this results in predicting, diagnosing and treating the subsequent obstructive sleep apnea. Forty patients who were diagnosed as skeletal Cl III maloccusion, received orthoganthic surgery of both jaws including mandibular setback, and were followed up post-operatively for more than 6 months were selected. There were 10 male patients 30 female patients. The preoperative and postoperative lateral cephalograms were traced and the distances and angles were measured. The nasopharyngeal space increased postoperatively while the oropharyngeal space decreased. Except for the change of oroparyngeal space, the changes in male patients were greater than female patients. The hyoid bone moved in the posterior-inferior direction, and the change was greater in males than in females. If the postoperative mandibular setback is great, then a significant decrease of airway space and posterior and inferior movement of the hyoid bone were observed. This can result in symptoms related to obstructive sleep apnea. This result should be considered in the diagnosis and treatment planning of orthognathic surgery patients.]]>
Diagnosis ; Female ; Humans ; Hyoid Bone ; Jaw ; Male ; Malocclusion ; Mandible ; Orthognathic Surgery ; Sleep Apnea, Obstructive