• 대한치과교정학회지
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• 제27권1호
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• pp.21-33
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• 1997

부산대학교병원 교정과에서 골격성 III급 부정 교합으로 진단되어 술전교정치료를 받고 악안면구강외과에서 악교정 수술을 받은 편악 수술군 18명과 양악 수술군 24명, 총 42명을 대상으로 초진, 수술 전, 수술 직후 및 수술 후 6개월 이상 경과 후에 채득한 측모두부방사선규격사진을 이용하여 분석하였다. 편악 수술군과 양악 수술군에서 치료과정에 따른 변화를 조사하여 악교정수술후 하악의 안정성에 영향을 미치는 요소를 알아보고자 분산분석을 기초로 하여 단계적 다중 희귀 분석을 시행하여 다음과 같은 결과를 얻었다. 1. 편악 수술군에서 수술에 의한 이동량, 하악전치 고경의 변화와 술전교정치료에 의한 하악평면각의 변화 및 하악전치의 경사도 변화가 악교정 수술후 하악의 안정성을 잘 설명하였고 결정계수는 0.84이었다. 2. 양악 수술군에서 수술에 의한 하악의 후방 이동량이 악교정 수술후 하악의 안정성을 설명하였고 결정계수는 0.28이었다.

• 대한치과교정학회지
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• 제47권3호
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• pp.195-206
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• 2017

Facial asymmetry can be classified into the rolling-dominant type (R-type), translation-dominant type (T-type), yawing-dominant type (Y-type), and atypical type (A-type) based on the distorted skeletal components that cause canting, translation, and yawing of the maxilla and/or mandible. Each facial asymmetry type represents dentoalveolar compensations in three dimensions that correspond to the main skeletal discrepancies. To obtain sufficient surgical correction, it is necessary to analyze the main skeletal discrepancies contributing to the facial asymmetry and then the skeletal-dental relationships in the maxilla and mandible separately. Particularly in cases of facial asymmetry accompanied by mandibular yawing, it is not simple to establish pre-surgical goals of tooth movement since chin deviation and posterior gonial prominence can be either aggravated or compromised according to the direction of mandibular yawing. Thus, strategic dentoalveolar decompensations targeting the real basal skeletal discrepancies should be performed during presurgical orthodontic treatment to allow for sufficient skeletal correction with stability. In this report, we document targeted decompensation of two asymmetry patients focusing on more complicated yaw-dependent types than others: Y-type and A-type. This may suggest a clinical guideline on the targeted decompensation in patient with different types of facial asymmetries.

• 구강회복응용과학지
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• 제40권2호
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• pp.91-99
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• 2024

골격성 3급 무치악 환자의 경우 총의치 제작 시 잔존치조제 관계를 고려하여 교차교합을 형성해 줌으로써 의치의 안정을 얻을 수 있다. 골격성 3급 악간관계에서 전치부를 정상교합 관계로 형성하는 것은 전방 캔틸레버를 가중시켜 의치의 안정을 저하시킬 수 있다. 하지만, 환자들은 총의치를 사용할 때 기능적인 면 뿐 아니라 심미적인 면 또한 중요시한다. 전치부 인공치들이 어떻게 배열되느냐에 따라 총의치의 심미성이 좌우되어, 골격성 3급 악간관계를 갖는 무치악 환자에서 정상교합이나 절단교합을 활용한 총의치 제작 증례가 보고되고 있다. 본 증례에서는 3급 악간관계를 갖는 무치악 환자에게 상악 전치부에 중립대를 고려하여 전치부 절단교합을 형성하여 의치를 제작하였고, 우수한 심미적, 기능적 결과를 얻었다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제33권3호
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• pp.218-224
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• 2011

Purpose: The purpose of this study is to evaluate the post-operative skeletal stability after surgical correction of patients with mandibular prognathism by bilateral sagittal split ramus osteotomy (BSSRO) and to evaluate the horizontal relapse tendency after the surgery. Methods: Twenty-six patients with Class III dental and skeletal malocclusion were selected for this retrospective study. Fifteen of them underwent BSSRO for mandibular setback and eleven of them underwent two-jaw surgery (Lefort I and BSSRO). In each patient, lateral cephalometric radiographs were taken pre-operatively, post-operatively within 1 week, and post-operatively after eight months. After tracing of the cephalometric radiographs, various parameters were measured. The analyses were done by linear measurement to evaluate the change in position of hard tissue B point, pogonion and mandibular plan angle by examination on lateral cephalograms. Results: The horizontal relapse rate was 27.1% at B point and 31.6% at pogonion in patients who underwent BSSRO. The horizontal relapse rate of the group where the amount of correction exceeded 10 mm was 25.69% at B point. Conclusion: There were no statistical differences on the magnitude of setback and direction of rotation of the mandible in mandibular stability. There were also no statistical differences between single mandibular surgery and two-jaw surgery for mandibular stability.

• 대한치과교정학회지
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• 제22권3호
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• pp.509-529
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• 1992

Skeletal Class III malocclusion is one of the most difficult type to treat and stabilize. For a child with developing skeletal Class III malocclusion, the treatment objective would be to stimulate maxillary growth, particulary one who has markedly deficient maxilla, and to restrain excessive mandibular growth. In order to stimulate the maxillary growth, maxillary protraction appliance is the one of the effective orthopedic appliances in skeletal Class III. The purposes of this study were as follows ; evaluation of the skeletal and dental changes of the maxillary protraction in children with Class III Maxillary deficiency , comparison of the clinical effects between the group with RPE and labiolingual intraoral appliances , comparison of the clinical effects and stability related to the ages of the patients : stability of the maxillary protraction about 1 year after retention. The subjects consisted of 60 children between the ages of 8 and 13.4 who were diagnosed as Class III with maxillary deficiency and were treated with Face Mask (Delaire Type) from the Dept. of Orthodontics Yong Dong Severance Hospital, Yonsei University. 48 children wore the RPE and 12 children wore Labiolingual Appliance. Lateral Cephalograms were taken for each patient at before and after correction of anterior cross-bite in 60 children, and after an observation period of 10 to 14 months in 19 children. X and Y coordinate of 10 landmarks were analyzed using a horizontal line through sella and rotated $6^{\circ}$ down anteriorly as the horizontal reference axis, and a perpendicular verticual line through sella as the vertical reference axis. Each of the 31 measurents (10 verticals, 10 horizontals, 2 angles and 9 others) was statistically analyzed using SPSS/PC statistics. The results are as follows; 1. After maxillary protraction the maxilla and maxillary teeth moved downward and forward, while the mandible and mandibular incisor rotated downward and backward. 2. Maxillary protraction with rapid palatal expansion appliance was more effective than with labiolingual appliance. 3. More downward movement of the posterior palatal plane obserbed with maxillary protraction doing the midpalatal suture opening than with protraction after finishing the palatal expansion 4. The clinical effects of protraction and changes of the retention periods were not statistically significant among the age groups. 5. During the retention period, maxilla and maxillary teeth, and mandible and mandibular teeth moved downward and forward, however the mandibular changes were larger than the maxillary changes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제43권1호
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• pp.23-28
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• 2017

Objectives: The purpose of this study is to compare the postoperative stability of conventional orthognathic surgery to a surgery-first orthognathic approach after bilateral sagittal split ramus osteotomy (BSSRO). Materials and Methods: The study included 20 patients who underwent BSSRO for skeletal class III conventional orthognathic surgery and 20 patients who underwent a surgery-first orthognathic approach. Serial lateral cephalograms were analyzed to identify skeletal changes before surgery (T0), immediately after surgery (T1), and after surgery (T2, after 1 year or at debonding). Results: The amount of relapse of the mandible in the conventional orthognathic surgery group from T1 to T2 was $2.23{\pm}0.92mm$ (P<0.01) forward movement and $-0.87{\pm}0.57mm$ (non-significant, NS) upward movement on the basis of point B and $2.54{\pm}1.37mm$ (P<0.01) forward movement and $-1.18{\pm}0.79mm$ (NS) upward movement on the basis of the pogonion (Pog) point. The relapse amount of the mandible in the surgery-first orthognathic approach group from T1 to T2 was $3.49{\pm}1.71mm$ (P<0.01) forward movement and $-1.78{\pm}0.81mm$ (P<0.01) upward movement on the basis of the point B and $4.11{\pm}1.93mm$ (P<0.01) forward movement and $-2.40{\pm}0.98mm$ (P<0.01) upward movement on the basis of the Pog. Conclusion: The greater horizontal and vertical relapse may appear because of counter-clockwise rotation of the mandible in surgery-first orthognathic approach. Therefore, careful planning and skeletal stability should be considered in orthognathic surgery.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제22권2호
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• pp.184-190
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• 2000

Objective : To compare two different methods of rigid fixation in postoperative stability after mandibular setback. Material and Methods : 28 patients with Class III malocclusion were treated by bilateral sagittal split ramus osteotomy(BSSRO) and mandibular setback were selected for this study. Group A(n=14) had the bone segments fixed with monocortical miniplate on the lateral side of the mandibular body and Group B(n=14) had three noncompressive bicortical screw inserted at the genial area through a transcutaneous approach. Cephalograms were taken preoperatively, postoperatively within 1 weeks and at a follow-up period (mean 8.9 months after surgery) and the amount of setback and postoperative change were measured. Results : Postoperative relapse between two groups was minimal in setback of the mandible. Statistical analysis showed no significant difference in postoperative relapse. Conclusion : This study suggests that both methods of skeletal fixation investigated give comparable postoperative stability and their use in mandibular setback appears to be a fairly stable clinical procedure .

• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권6호
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• pp.485-491
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• 2009

Postoperative skeletal stability was evaluated in combination of Le Fort I and U-shaped osteotomies for superior repositioning of maxilla in bi-maxillary surgeries in 30 consecutive patients. The fifteen patients underwent Le Fort I osteotomy alone and the other fifteen patients underwent Le Fort I and U-shaped osteotomies. In all patients, the maxilla was first osteomized and fixed with absorbable plates system. A bilateral sagittal split ramus osteotomy (BSSRO) of the mandible was then carried out and fixation was performed using absorbable plates. Maxillo-mandibular fixation with rubber ring was used for two weeks post-operatively in all patients. Lateral cephalograms were obtained pre-operatively, 1 day post-operatively, 6 months after surgery. The changes in anterior nasal spine (ANS), point A, upper incisior (U1), and point of maxillary tuberosity (PMT) were examined. The maxillas in the fifteen patients of both examination group were repositioned nearly in their planned positions during surgery and no significant post-operative changes in the examined points of the maxilla were found. These results suggest that a combination of a Le Fort I and U-shaped osteotomy is a useful technique for reliable superior repositioning of the maxilla. The post-operative change in the maxilla using this combination osteotomy was comparatively stable.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제18권4호
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• pp.563-569
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• 1996

Skeletal and dental changes were examined in 38 patients of mandibular prognathism who been treated by a bilateral sagittal split osteotomy(SSRO) and internal fixation using titanium mini-screws. All patients were followed up for over 8 months after the surgeries, and postoperative cephalometric measurements were compared at 2 months and at 8 months. Linear measurements of the "Pog-most posterior screws" and angular measurementsts of "SN-Pog'were compared to figure out the change of bony fragments. The significancy of data were tested by unpaired T-test. The results were as follows : 1. The fixation screws were changed in cephalometric position as little as $0.32{\pm}2.51mm$ in SSRO and $0.15{\pm}1.00mm$ in SSRO & Le Fort I Osteotomy.(P<0.05) 2. Mandibular set-back over 5mm resulted in less stability of the fixation screws and higher relapse tendency. 3. The internal fixation using two screws along the inferior border and one on the superior ridge is considered to be very resistant to postoperative relapse of the repositioned bony segments.

• Asian-Australasian Journal of Animal Sciences
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• 제22권2호
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• pp.282-288
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• 2009

The present paper describes the effects of pressure and post-mortem aging treatments on in situ proteasome activity in rabbit and bovine skeletal muscles. Synthetic peptide hydrolyzing activity of rabbit proteasomes remained in the muscle after exposure to pressures up to 100 MPa. However, when a pressure of 400 MPa or more was applied, proteasomes were markedly inactivated. The extraction of proteasomes from excessively pressurized muscle appeared to be difficult. Proteasomes in aged muscle remained relatively stable throughout the aging process, with activity after 168 h (7 days) being 35%, 48%, 53% and 31% of the 0 h post-mortem LLVY, LSTR, AAF and LLE total hydrolyzing activities, respectively. The synthetic peptide hydrolyzing activities of bovine muscle proteasomes were similar to those of rabbit skeletal muscle proteasomes. The results suggest that synthetic peptide hydrolyzing activity remains in muscle exposed to relatively low pressures. Furthermore, it is known that high-pressure treatment induces fragmentation of myofibrils, modification of actin-myosin interaction and activation of intramuscular proteinases, cathepsins and calpains. Thus, proteasomes are probably involved in the tenderization process in combination with other intramuscular proteinases under high-pressure conditions. Our findings confirmed that proteasomes play a role in meat tenderization induced by high-pressure treatment or aging.