• Maxillofacial Plastic and Reconstructive Surgery
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• 제40권
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• pp.13.1-13.8
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• 2018

Background: We evaluated change in the mandibular condyle after orthognathic surgery using cone-beam computed tomography (CBCT) in patients with facial asymmetry. Methods: Thirty patients with skeletal class III malocclusion and mandibular prognathism or facial asymmetry were classified into two groups according to the amount of menton deviation (MD) from the facial midline on anteroposterior (AP) cephalogram: group A (asymmetry, MD ≥ 4 mm; n = 15) and group B (symmetry, MD < 4 mm; n = 15). Position and angle of condylar heads on the axial, sagittal, and coronal views were measured within 1 month preoperatively (T0) and postoperatively (T1) and 6 months (T2) postoperatively. Results: On axial view, both groups showed inward rotation of condylar heads at T1, but at T2, the change was gradually removed and the condylar head returned to its original position. At T1, both groups showed no AP condylar head changes on sagittal view, although downward movement of the condylar heads occurred. Then, at T2, the condylar heads tended to return to their original position. The change in distance between the two condylar heads showed that they had moved outward in both groups, causing an increase in the width between the two heads postoperatively. Analysis of all three-dimensional changes of the condylar head positions demonstrated statistically significant changes in the three different CBCT views in group B and no statistically significant changes in group A. Conclusions: There was no significant difference between the two groups in condylar head position. Because sagittal split ramus osteotomy can be performed without significant change in symmetrical and asymmetrical cases, it can be regarded as an effective method to stabilize the condylar head position in patients with skeletal class III malocclusion and mandibular prognathism or facial asymmetry.

• Imaging Science in Dentistry
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• 제41권3호
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• pp.95-100
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• 2011

Purpose : The purpose of this study was to compare asymmetric mandibular prognathism individuals with symmetric mandibular prognathism individuals using a new alternate spherical coordinate system. Materials and Methods : This study consisted of 47 computed tomographic images of patients with mandibular prognathism. The patients were classified into symmetric and asymmetric groups. Mandibular and ramal lines were analyzed using an alternate spherical coordinate system. The length as well as midsagittal and coronal inclination angle of the lines was obtained. The bilateral differences of the spherical coordinates of the facial lines were statistically analyzed in the groups. Results : There were significant differences between the groups in bilateral difference of the length and midsagittal inclination angle of the lines (p<0.05). The bilateral difference of the length and midsagittal inclination angle of the lines has significant correlation with chin deviation (p<0.05). Conclusion : The new alternate spherical coordinate system was able to effectively evaluate facial lines. The bilateral difference of lengths and midsagittal inclination of the facial lines might contribute to the facial asymmetry in mandibular prognathism individuals.

• 대한두개안면성형외과학회지
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• 제11권1호
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• pp.45-48
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• 2010

Purpose: After surgical interventions of mandible fractures, facial asymmetry can be occurred, and it leads to serious problems for patients. This can be solved by mandible angle ostectomy. Methods: A 19-year-old male underwent percutaneous surgical intervention for left mandibular angle and right parasymphyseal fractures 3.5 years ago. The left angle was protruded compared to the other side. Using a percutaneous approach, $4.5{\times}1cm$ sized piece of mandible angle was sawed off. For the right angle, intraoral approach was performed for angle ostectomy, and the angle was sawed off by a size of $4{\times}1cm$, using a pattern based on the piece from the left side. Results: After surgery, no complications such as subcondylar fractures, refractures, insufficient corrections, secondary angle formations, hematomas, and transient nerve palsies were seen, and symmetric correction of mandible angles were done. Conclusion: In facial asymmetries due to mandibular fractures, mandible ostectomy could be a solution. Using the bone section from the contralateral side, measurement of the amount of bone sawed off was possible, and via percutaneous approach on the previously operated site with simultaneous scar revision, and intraoral approach for the contralateral side, cosmetically satisfactory result was obtained.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제13권2호
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• pp.191-198
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• 1991

안모비대칭은 심미적 정서적으로 영향을 줄 뿐만 아니라 기능적인 장애를 초래하는 경우도 있다. 안모비대칭은 안면골 중에서 특히 하악골과 관련된 경우가 많은데 이는 하악골이 안면하부의 연조직을 지지하므로 작은 위치, 형태 변화에도 두드러지게 나타나기 때문이다. 비대칭안모를 초래하는 하악과두의 거대증은 Hyperplasia, Hypertrophy, 골증, 외골증, 골연골증, 연골육종 등을 들 수 있다. 비대칭안모 분류는 여러 학자에 의해 다양하게 분류되지만 Bruce와 Hayward는 Deviation prognathism, Unilateral macroganthia, Unilateral condylar hyperpiasia로 분류한 바 있다. 과증식된 하악과두의 절제술은 1856년 Humphry에 의해 최초로 시행된 후 여러 학자들에 의해 성공적으로 시행되고 있다. 본 증례에서는 Unilateral condylar hyperlpasia와 골연골종으로 인한 안모비대칭 환자로써 Condylectomy, Le Fort I osteotomy, Vertical ramus osteotomy, Mandibular inferior border ostectomy, Genioplasty 등을 시행하여 심미적 기능적으로 양호한 결과를 얻었기에 이를 보고하는 바이다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제40권1호
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• pp.32-36
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• 2014

Preoperative surgical simulation in orthognathic surgery has progressed in recent years; the movement of the mandible can be anticipated through three-dimensional (3D) simulation surgery before the actual procedure. In this case report, the mandible was moved to the intended postoperative occlusion through preoperative surgical 3D simulation. Right-side condylar movement change was very slight in the surgical simulation, suggesting the possibility of mandibular surgery that included only left-side ramal osteotomy. This case report describes a patient with a mild asymmetric facial profile in which the mandibular menton had been deviated to the right and the lips canted down to the left. Before surgery, three-dimensional surgical simulation was used to evaluate and confirm a position for the condyle as well as the symmetrical postoperative state of the face. Facial asymmetry was resolved with minimal surgical treatment through unilateral intraoral vertical ramus osteotomy on the left side of the mandible. It would be a valuable complement for the reduction of the surgical treatment if one could decide with good predictability when an isolated intraoral vertical ramus osteotomy can be done without a compensatory osteotomy on the contralateral side.

• 구강회복응용과학지
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• 제17권4호
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• pp.225-230
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• 2001

Morphological characteristics of the asymmetric mandible in 135 adult male patients were investigated. Panoramic X-ray images were recorded. Age, ramus height, antegonial notch height, condylar height, coronoid process height, ramus body height and condylar neck angle were calculated and measured. Statistical analysis of unpaired two-tailed t-test and correlation coefficients was performed to find the morphologic differences between short ramus height side and the other. Condylar height and ramus body height in short ramus height side were smaller than those of the other side. Antegonial notch height, coronoid process height, condylar neck angle showed no differences. Condylar neck height was correlated with condylar neck angle.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제31권6호
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• pp.526-531
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• 2005

Distraction osteogenesis is a technique of bone lengthening by gradual movement and subsequent remodeling. Distraction forces applied to bone also create tension in the surrounding soft tissues, distraction histiogenesis. Distraction osteogenesis is used to correct facial asymmetry, such as patients with hemifacial microsomia, maxillary or mandibular retrusion, cleft lip & palate, alveolar defect and craniofacial deficiency. Hemifacial microsomia is characterized by unilateral facial hypoplasia, often with unilateral shortening of the mandible and subsequent malocclusion. This report describes two cases of hemifacial microsomia(type IIB). In these two cases, distraction osteogenesis was used to correct a facial asymmetry. Two patients underwent unilateral mandibular distraction osteogenesis of ascending ramus of the mandible with extraoral devices. Successful distraction osteogenesis was achieved in the patients with hemifacial microsomia.

• 대한치과교정학회지
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• 제53권2호
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• pp.99-105
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• 2023

Objective: The study aimed to evaluate the changes in mandibular width after sagittal split ramus osteotomy (SSRO) in patients with mandibular asymmetric prognathism using cone-beam computed tomography (CBCT). Methods: Seventy patients who underwent SSRO for mandibular setback surgery were included in two groups, symmetric (n = 35) and asymmetric (n = 35), which were divided according to the differences in their right and left setback amounts. The mandibular width was evaluated three-dimensionally using CBCT images taken immediately before surgery (T1), 3 days after surgery (T2), and 6 months after surgery (T3). Repeated measures analysis of variance was applied to verify the differences in mandibular width statistically. Results: Both groups showed a significant increase in the mandibular width at T2, followed by a significant decrease at T3. No significant difference was observed between T1 and T3 in any of the measurements. No significant differences were found between the two groups (p > 0.05). Conclusions: After mandibular asymmetric setback surgery using SSRO, the mandibular width increased immediately but returned to its original width 6 months after surgery.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제40권5호
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• pp.205-205
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• 2014

• 대한치과교정학회지
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• 제21권3호
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• pp.701-709
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• 1991

This paper presents 2 clinical cases of facial asymmetry resulted from vertical asymmetry of the maxilla and unilateral hyperplasia of the mandibular condyle. Both patients, a 27 year 4 month old female and a 17 year 1 month old male, had a anterior crossbite with deviated dental midline and a concave profile. Both cases were treated with orthodontic and orthognathic procedure. The following results were obtained; 1. The facial asymmetry was favorably corrected. 2. The concave profile was improved. 3. The anterior crossbite was corrected. 4. The upper and lower dental midlines against the facial midline were corrected. 5. The functional overbite and overjet were established.