• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권6호
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• pp.628-634
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• 2008

The purpose of this study is to examine reproducibility of operation plan and 3-dimentional jaw movement patterns by comparing jaw position of STO with post-operative jaw position. Twenty patients with class III dental and skeletal malocclusion who were treated with Le-Fort I osteotomy and B-SSRO were reviewed. Lateral cephalometric radiographs were taken within two weeks before operation and two days after operation. Cephalometric radiographs were compared and analyzed with orthognathic computer program '$V-Ceph^{TM}$'. Post-operative maxillary advancement was insufficient compared to maxillary advancement through STO. Post-operative setback movement was over compared to mandibular setback movement through STO. But statistically this is not significant. Maxillary vertical location is insignificant on the whole. Especially post-operative maxillary clockwise rotation is significant compared to maxillary rotation through STO. Post-operative maxillary clockwise rotation tendency is generally observed in all patients. So surgeons and staffs must consider this tendency when operation plan is established ans operation is being performed. Using intra or extra oral marking points, face bow, and bite plate will make exact surgery possible.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제38권1호
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• pp.9-13
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• 2012

Introduction: To evaluate the 3-dimensional changes in the pharyngeal airway of skeletal class III patients after bimaxillary surgery. Materials and Methods: The study sample consisted of 18 Korean patients that had undergone maxillary setback or posterosuperior movement and mandibular bilateral sagittal split osteotomy setback surgery due to skeletal class III malocclusion (8 males, 10 females; mean age of 28.7). Cone beam computed tomography was taken 1 month before and 6 months after orthognathic surgery. Preoperative and postoperative volumes of the nasopharyngeal, oropharyngeal, and laryngopharyngeal airways and minimum axial areas of the oropharyngeal and laryngopharyngeal spaces were measured. Moreover, the pharyngeal airway volume of the patient group that had received genioplasty advancement was compared with the other group that had not. Results: The nasopharyngeal and laryngopharyngeal spaces did not show significant differences before or after surgery. However, the oropharyngeal space volume and total volume of pharyngeal airway decreased significantly (P<0.05). The minimum axial area of the oropharynx also decreased significantly. Conclusion: The results indicate that bimaxillary surgery decreased the volume and the minimum axial area of the oropharyngeal space. Advanced genioplasty did not seem to have a significant effect on the volumes of the oropharyngeal and laryngopharyngeal spaces.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제27권4호
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• pp.334-345
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• 2005

The purpose of this study was to compare the postoperative stability and relapse according to 2 different fixation methods after bilateral sagittal split ramus osteotomies in mandibular prognathic patients. Tweenty one patients with Class III dental and skeletal malocclusion who were treated with bilateral sagittal split ramus osteotomy were selected for this retrospective study. We classfied the patients into two groups according to the fixation methods of bony segments after osteotomies. Group W (n = 10) had the bone segments fixed with nonrigid wire and Group S (n = 11) had bicortical screws inserted in the gonial area through a transcutaneous approach. Cephalometric radiographs were taken preoperatively, immediate postoperatively and more than six months postoperatively in each patient. After tracing the cephalometric radiographs, various parameters were measured. Before surgery, both groups were balanced with respect to linear and angular measurements of craniofacial morphology. Mean posterior sagittal setback amounts of the mandibular symphysis was 8.6 mm in the wire group and 6.79 mm in the rigid group, Six months postoperatively, the wire group had 33.1% relapse of the mandibular symphysis and 22.8% in the rigid group relapse. Both groups experienced changes in the orientation and configuration of the mandible. It is thought that Rigid screw fixation is a more stable method than nonrigid wire fixation for maintaining mandibular setback after sagittal split ramus osteotomy.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제16권1호
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• pp.51-62
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• 1994

The sagittal split osteotomy of the mandibular ramus is a common procedure which has been used in the correction of mandibular deformities for a few decades. Although the technical improvements have increased the reliability and stability of SSRO procedure, the postoperative relapse is imperative and clinically more significant than any other complication. One of the major causes of the relapse is due to the displacement of the proximal segment during SSRO procedure, which is well documented in the literature. Therefore it is important to preserve the original position of the proximal segment during SSRO proced and maxillofacial fixation period. In the case of mandibular asymmetry, if one side of mandible is advanced and the other side of mandible is setback during SSRO procedure, the proximal segment in the advancement site will rotate laterally and the proximal segment in the setback site will rotate medially. For the prevention of the lateral rotation or flaring of the proximal segment in the advancment site. we deliberately fracture the posterior protion of the distal segment in green-stick fashion during SSRO procedure, and there is no need to fix the fractured lingual segment. We fix the two osteotomized bony segments in the buccal cortex area rigidly with adjustable monocortical plates and screws. During SSRO procedure the lingual fracture technique was applied to nine patients with severe mandibular asymmetry who underwent orthognathic surgery in our hospital since march, 1992. These clinical experiencies enable us to find the lingual fracture technique has the following advantages. 1. The proximal segment is displaced minimally. 2. The osteotomized bony segments are contacted intimately. 3. The postoperative relapse and the healing period are decreased.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제36권5호
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• pp.185-191
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• 2014

Purpose: Although there have been several studies of reduced airway space after mandibular setback surgery using the sagittal split ramus osteotomy technique, research on the risk factors for changes of the airway space is lacking. Therefore, this study was performed to examine airway changes and the position of the hyoid bone after orthognathic surgery, and to assess possible risk factors. Methods: In this retrospective study, 50 patients who underwent posterior displacement of the mandible by the bilateral sagittal split ramus osteotomy technique were included. Changes of the position of the hyoid bone and the airway space were analyzed over various follow-up periods, using cephalometric radiography taken preoperatively, immediately after surgery, eight weeks after surgery, six months after surgery, and one year after surgery. To identify risk factors, multiple regression analysis of age, gender, body mass index (BMI), posterior mandibular movement, and the presence of genioplasty was performed. Results: Inferor and posterior movement of the hyoid bone was observed postoperatively, but subsequent observations showed regression towards the anterosuperior aspect. The airway space also significantly decreased after surgery (P<0.05), and increased slightly up until six months after surgery. The airway space significantly decreased (${\beta}=0.47$, P<0.01) as the amount of mandibular setback increased. However, age, sex, BMI, and presence of genioplasty were not associated with airway reduction. Conclusion: The amount of mandibular set back was significantly associated with postoperative reduction of airway space. It is necessary to establish a treatment plan considering this factor.

• 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.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제38권
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• pp.47.1-47.8
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• 2016

Background: The paradigm of tonsillectomy has shifted from a treatment of recurrent throat infection to one of multi-discipline management modalities of sleep-disordered breathing (SDB). While tonsillectomy as a treatment for throat problems has been performed almost exclusively by otorhinolaryngologists, tonsillectomy as a part of the armamentarium for the multifactorial, multidisciplinary therapy of sleep-disordered breathing needs a new introduction to those involved in treating SDB patients. This study has its purpose in sharing a series of tonsillectomies performed at the Seoul National University Dental Hospital for the treatment and prevention of SDB in adult patients. Methods: Total of 78 patients underwent tonsillectomy at the Seoul National University Dental Hospital from 1996 to 2015, and 23 of them who were operated by a single surgeon (Prof. Jin-Young Choi) were included in the study. Through retrospective chart review, the purpose of tonsillectomy, concomitant procedures, grade of tonsillar hypertrophy, surgical outcome, and complications were evaluated. Results: Twenty-one patients diagnosed with SDB received multiple surgical procedures (uvulopalatal flap, uvulopalatopharyngoplasty, genioglossus advancement genioplasty, tongue base reduction, etc.) along with tonsillectomy. Two patients received mandibular setback orthognathic surgery with concomitant tonsillectomy in anticipation of postoperative airway compromise. All patients showed improvement in symptoms such as snoring and apneic events during sleep. Conclusions: When only throat infections were considered, tonsillectomy was a procedure rather unfamiliar to oral and maxillofacial surgeons. With a shift of primary indication from recurrent throat infections to SDB and emerging technological and procedural breakthroughs, simpler and safer tonsillectomy has become a major tool in the multidisciplinary treatment modality for SDB.

• 한국식품영양과학회지
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• 제34권1호
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• pp.87-92
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• 2005

찰흑미(상해항혈나) 전분의 호화 특성을 알아보고자 신선찰벼 전분을 대조구로 SEM, X-ray 회절도, 시차주사열량계와 신속점도계를 이용하여 호화특성을 비교하였다. 주사전자현미경에 의한 입자형태의 변화에서는 6$0^{\circ}C$에서 찰흑미 전분에 비해 신선찰벼 전분의 입자 붕괴가 더 심하였으며, 시 차주사열량계에 의한 관찰에서는 신선찰벼와 찰흑미 전분의 호화개시온도는 62.$0^{\circ}C$와 63.$0^{\circ}C$, 피크온도는 69.$0^{\circ}C$, 69.4$^{\circ}C$, 호화절정온도는 78.7$^{\circ}C$, 78.9$^{\circ}C$, 호화엔탈피는 각각 8.55 J/g, 8.87 J/g로 서로 차이를 보이지 않았다. 생 전분의 X-선 회절양상은 두 시료 모두 전형적인 A형을 보였고, 가열온도에 따른 양상에 있어서 6$0^{\circ}C$ 및 $65^{\circ}C$에서 신선찰벼 전분에 비해 찰흑미 전분의 결정형이 상대적으로 많음을 알 수 있었으나 $65^{\circ}C$를 경계로 결정형 영역은 완전히 사라졌다. 신속점도계를 이용한 호화특성에서는 최고점도, breakdown, 최종점도, setback은 시료간에 큰 차이를 보이지 않았다.

• 한국식품과학회지
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• 제42권3호
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• pp.292-297
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• 2010

도복 현미와 백미 곡립의 경도는 도복 시간에 따라 감소하였고, 무도복 현미와 백미의 경도는 오히려 증가하였다. 도복 현미와 백미의 DSC 열적 성질($T_o$, $T_p$, $T_c$, ${\Delta}H$)은 도복 시간에 따라 감소하였고, 무도복 현미와 백미의 경우는 증가하였다. 현미 백미 곡립의 경도와 DSC 열적 성질, 특히 ${\Delta}H$와 $T_p$는 밀접한 상관관계를 보였다. 도복 현미와 백미의 RVA 호화 특성(최대점도, 최저점도, 최종점도, breakdown, consistency)은 도복 시간에 따라 감소하였고, 무도복 현미와 백미의 경도는 오히려 증가하였다. 다만 setback의 경우는 일정한 경향을 보이지 않았다. 도복 현미밥과 백미밥의 경도, 응집성, 검성, 씹음성, 부착성, 탄성은 도복 시간에 따라 감소하였고, 무도복 현미밥과 백미밥의 경우는 증가하였다. 다만 응집성과 부착성은 백미가 현미보다 높았다.

• 한국식품조리과학회지
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• 제25권2호
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• pp.199-205
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• 2009

울금가루를 새로운 식품소재로 활용하고자 하는 연구의 일환으로 울금가루 첨가량을 달리하여 국수를 제조하고 그 품질특성을 조사하였다. 밀가루와 울금가루 혼합분의 물결합력과 breakdown은 울금가루 8% 첨가구에서 가장 높았으나, setback은 울금가루 8% 첨가구에서 가장 낮았다. 울금가루 첨가 국수의 조리 특성에서 무게, 부피 및 인장강도는 울금가루 8% 첨가구에서 가장 낮았고, 대조구에서 가장 높았으나, 탁도는 울금가루 8% 첨가구에서 가장 높았으며, 울금가루 첨가량이 증가할수록 높았다. 국수의 조리 전과 조리 후의 색도 및 물성의 변화에서 L값은 조리 전 생국수가 조리된 국수보다 높았으나, 색도의 a값 및 b값과 물성에서는 조리 전 생국수보다 조리된 국수에서 높았다. 색도의 L값과 물성의 탄력성 및응집성은 울금가루 첨가량이 증가할수록 낮아졌고, 색도의 a값 및 b값과 물성의 경도, 점착성 및 씹힘성은 울금가루 첨가량이 증가할수록 높아졌다. 울금가루 첨가량에 따른 관능검사에서 울금가루 4% 첨가구의 기호도가 가장 높았고, 울금가루 2% 및 8% 첨가구는 대조구보다 낮은 기호도를 보였다.