• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권2호
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• pp.164-171
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• 2000

Purpose : This study was aimed at measuring the changes in the hyoid bone position, tongue position, and pharyngeal airway space in subjects with mandibular setback osteotomies. Methods : Twenty patients were evaluated retrospectively for their changes in pharyngeal airway space, tongue and hyoid bone positions. All patients underwent surgical mandibular setback using bilateral sagittal split osteotomies. The cephalometric analysis was performed preoperatively, and 1 week, 3-6 months, and 1 year postoperatively. Result : The hyoid bone moved inferiorly and posteriorly immediately after surgery, and it returned to the preoperative position during follow-up period. The nasopharyngeal airway space was not significantly changed after surgery. A considerable decrease in the oropharyngeal and hypopharyngeal airway spaces following mandibular setback surgery was found. The upper and lower tongue was posteriorly repositioned immediately after surgery. During follow-up period, the hypopharyngeal airway space and lower tongue posture returned to the preoperative positions, but the oropharyngeal airway space and upper tongue posture were not significantly changed. The position of pogonion remarkably changed to backward immediately after surgery, but slightly anterior advancement was found during follow-up period. Conclusion : Immediately after mandibular setback surgery, the oropharyngeal and hypopharyngeal airway spaces obviously decreased due to posterior and inferior repositions of the tongue and hyoid bone. During follow-up period, lower tongue and hyoid bone returned to the preoperative positions, it was related to advancement of the pogonion in this period. The narrowing of the oropharyngeal airway space and posterior movement of the upper tongue posture were relatively permanent after mandibular setback surgery. We suspected this phenomenon had an influence on maintaining the total volume of oral cavity against mandibular setback.

• Journal of Yeungnam Medical Science
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• 제5권2호
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• pp.71-77
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• 1988

Adenoids 비인두폐쇄로 인해 구호흡이 유발된 6~12세의 아동 50명과 동일 연령분포의 정상아동 50명의 두부방사선 계측사진을 통해 Tongue, Mandible 및 Hyoid bone에 대한 수평, 수직 및 각도 계측에 대한 비교 연구 결과 다음과 같은 결론을 얻었다. 1. Tongue position은 실험 군에서 더 전하방 위치하는 것으로 관철되었다. 2. Mandibular position은 실험군에서 더 하방위치 하는 것으로 관찰되었다. 3. Hyoid bone의 위치는 실험군에서 더 전하방위치하는 것으로 관찰되었다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제42권
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• pp.27.1-27.9
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• 2020

Background: Mandibular setback surgery can change the position of the mandible which improves occlusion and facial profile. Surgical movement of the mandible affects the base of the tongue, hyoid bone, and associated tissues, resulting in changes in the pharyngeal airway space. The aim of this study was to analyze the 3-dimensional (3D) changes in the hyoid bone and tongue positions and oropharyngeal airway space after mandibular setback surgery. Methods: A total of 30 pairs of cone-beam computed tomography (CBCT) images taken before and 1 month after surgery were analyzed by measuring changes in the hyoid bone and tongue positions and oropharyngeal airway space. The CBCT images were reoriented using InVivo 5.3 software (Anatomage, San Jose, USA) and landmarks were assigned to establish coordinates in a three-dimensional plane. The mean age of the patients was 21.7 years and the mean amount of mandibular setback was 5.94 mm measured from the B-point. Results: The hyoid bone showed significant posterior and inferior displacement (P < 0.001, P < 0.001, respectively). Significant superior and posterior movements of the tongue were observed (P < 0.05, P < 0.05, respectively). Regarding the velopharyngeal and glossopharyngeal spaces, there were significant reductions in the volume and minimal cross-sectional area (P < 0.001). The anteroposterior and transverse widths of the minimal cross-sectional area were decreased (P < 0.001, P < 0.001, respectively). In addition, the amount of mandibular setback positively correlated with the amount of posterior and inferior movement of the hyoid bone (P < 0.05, P < 0.05, respectively). Conclusion: There were significant changes in the hyoid bone, tongue, and airway space after mandibular setback surgery.

• 대한치과교정학회지
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• 제16권2호
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• pp.99-106
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• 1986

The author studied 21 adenoid hypertrophied children and 50 normal children by the horizontal, vertical and angular measurements to analyze, the effects of the lymphadenoid hypertrophy to the tongue, mandible, and hyoid bone position. The results were as follows; 1. The tongue of the Adenoid hypertrophy children was positioned mon anterior and lower than that of the normal children. 2. The horizontal, vertical, and angular measurements of the mandible position were larger in the experimental group and especially ANS to ME, PNS to MP, PTM to MP, PP to MP, FOP to MP showed statistically significant difference. 3. The measurements of the hyoid bone position were also larger in the experimental group.

• 대한치과교정학회지
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• 제27권2호
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• pp.231-243
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• 1997

본 연구는 거대 편도를 가진 기능성 III급 부정 교합자의 구대 편도 절제술 전후의 인두강, 설골, 두부 위치의 변화 양상에 대해 알아보기 위해 단국 대학교 부속 치과 병원 교정과에 내원한 남녀 환자 42명을 대상으로 연구하여 다음과 같은 결론을 얻었다. 1. Enlarged tonsil을 보이는 기능성 3급 부정교합자는 1급 부정교합자보다 혀는 전방에 위치하고 설골은 하방에 위치한다. 2. Tonsillectomy 후에 편도 절제술전과 비교하여 혀는 후방에 위치하고, nasopharynx은 증가 양상을 보이며, 설골은상, 후방에 위치하며 counterclockwise rotation 양상을 보인다. 3. Tonsillectomy 후에 nasopharynx depth변화와 하악 전치 경사도, 혀의 수직적 변화와 cranial base에 대한 hyoid axis, hyoid의 수직적, 수평적 변화와 두경부 경사도, 두경부 경사도와 하악 전치간에 95% 유의수준으로 상관성을 보인다. 4. Tonsillectomy 후에 설골 장축의 counterclockwise rotation시 hya-NL의 감소와 nasopharyx의 증가를 보이고, 혀의 거상시 hya-NL의 감소를 보이며, 혀의 후방위치시 h-h1의 증가와 hya-ba-n의 감소를 보인다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권4호
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• pp.294-305
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• 2009

Purpose: This retrospective study evaluated the changes in hyoid bone and tongue positions as well as oral cavity volume after mandibular setback by BSSRO. Materials and Methods: 18 Koreans who underwent BSSRO to correct mandibular prognathism were studied. Lateral cephalograms were taken and traced preoperatively (T0), immediately (T1) and approximately 6 months postoperatively (T2). Submentovertex radiograghs were taken and traced before surgery (T0) and about 6 months after surgery (T2). The area and volume of oral cavity, the vertical and horizontal dimensions of the hyoid bone and tongue dorsum were measured. Results: Mandibular setback surgery resulted in a significant reduction of lower oral cavity volume. The hyoid bone displaced posteroinferiorly immediately after surgery, and it tended to return to its original vertical position at 6 month after mandibular setback by BSSRO. The retropalatal space around tongue was maintained and the retrolingual space around tongue was reduced immediately postoperatively. The readaptation of tongue was not evident for that the follow up period was not long enough. No significant statistical correlations between the amounts of mandibular setback and the changes of oral cavity volume were observed. Conclusion: Mandibular setback surgery resulted in a significant reduction of lower oral cavity volume, which was most likely attributable to the posterior movement of the mandible. More subjects and long-term observations should be performed to assess the changes of oropharyngeal configuration following mandibular setback surgery.

• 대한치과교정학회지
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• 제17권1호
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• pp.7-13
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• 1987

This study was conducted to clarify the relationship of hyoid bone position to tongue position and mandible when malocclusion is categorized in the bilateral and in the vertical components. Five groups of samples (normal occlusion, unilateral and bilateral cross-bite, openbite, deep-bite) were selected for his investigation by utilizing the cephalograms. On the basis study, the following conclusions were obtained; 1. In the normal group. the mean hyoid position (H-M) was $9.83{\pm}4.27mm$. The mean distance of hyoid body to tongue dorsum (H-T) was $52.17{\pm}6.70mm$. The ratio of H-M/H-T was $18.59\%$. 2. In all malocclusion groups, the hyoid position (H-M) was found to be larger than that of the norm except the deep overbite group 3. The tongue dorsum position (H-T) was increased, compared to that of norm, in all malocclusion groups. 4. Hyoid position (H-M) was found to show high correlation to the ratio of H-M/H-T, H-T, PI-T (0.890, 0.699, 0.455). 5. The hyoid position (H-M) was found to show low correlation to the measurements of mandible, but among them the ODI was found to show conversely a little higher correlation against hyoid position (H-M).

• 대한치과교정학회지
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• 제30권5호
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• pp.579-589
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• 2000

혀와 설골의 위치가 안모형태와 어떤 양태로 상관성을 갖는지 비교평가하기 위해 69명의 성인군과 63명의 성장군에서 두부방사선계측사진을 얻었다. 성인군과 성장군에서 SN평면에 대해 큰 하악평면각을 갖는 군과 작은 하악평면각을 갖는 군으로 구분하여 다음과 같은 결론을 얻었다. 1. 혀의 높이는, 큰 하악평면각을 갖는 군보다는 작은 하악평면각을 갖는 군에서, 성인군보다는 성장군에서 높게 나타났다. 2. 설골의 수직적 높이는 큰 하악평면각을 갖는 군보다는 작은 하악평면각을 갖는 군에서, 성인군보다는 성장군에서 높게 나타났다. 3. 연령과 안모형태의 수직적 분류에 따른 설골의 전후방적인 위치는 차이가 없었다. 4. 두개저에 대한 설골의 기울기에 있어, 성인군보다 성장군에서 좀 더 가파른 경사도를 갖고 있었다.

• 대한치과교정학회지
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• 제23권4호
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• pp.693-705
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• 1993

The purpose of this study was to investigate the functional adaptation of the tongue, the hyoid bone, the digastric muscle and the upper airway and the variables predicting postoperative stability following orthognathic surgery in patients with mandibular prognathism. 18 patients were selected(8 men and 10 women) for this study, who had received orthognathic surgery. Their lateral cephalograms, those were taken preoperatively, immediate postoperatively and over 6 months follow-up, were traced and analysed. The results were as follows : 1. The downward displacement of the hyoid bone and extended head posture were recognized, right after operation. Statistically significant correlations were found between the changes of the mandibular position and the digastric muscle and the change of head posture during operation. 2. The tongue was displaced downward following the hyoid displacement postoperatively. Statistically significant correlations were found between the change of the mandibular position and the change of the distance of the tongue and hard palate, and between the change of head posture and the changes of the upper airway sizes, the digastric muscle and the hyoid position during over 6 month's follow-up. 3. The change of the distance of the tongue and hard palate was the most significant factor for prognosis during over 6 month's follow-up. 4. There were no variables before operation to predict the postoperative stability and the constriction of the upper airway.

• 치과방사선
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• 제24권2호
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• pp.347-359
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• 1994

The reproducibility of cephalography in repeated exposures were studied by tracing and photographic subtraction. The materials consisted of 50 pairs of 'same day' radiograph taken under identical conditions. The evaluation included skull, cervical column, hyoid bone, pharynx, tongue, soft tissue profile resulting 43 items in tracing, and 19 items in photographic subtraction. The results obtained from the differences between each pair were as follows: 1. The means and standard deviations by tracing of skull, cervical column, hyoid bone, pharynx, tongue, soft tissue profile were 0.34±0.62㎜, 1.02±1.59㎜, 1.37±1.78㎜, 0.55±1.16㎜, 0.51±1.51㎜, 0.15±0.3㎜ each. 2. The means and standard deviations by photographic subtraction of skull, cervical column, hyoid bone, pharynx, tongue were 0.09±0.35㎜, 0.70±0.95㎜, 1.22±1.33㎜, 0.53±0.86㎜, 0.27±0.41㎜ each.