• 대한치과교정학회지
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• 제45권4호
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• pp.180-189
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• 2015

Objective: To compare the positions of the mandibular premolars in Angle Class I subjects according to vertical facial type. The results will provide a theoretical basis for predicting effective tooth movement in orthodontic treatment. Methods: Cephalometric parameters were determined using cone-beam computed tomography in 120 Angle Class I subjects. Subjects were categorized as short, normal, and long face types according to the Frankfort mandibular angle. Parameters indicating the position of the mandibular right premolars and the mandible were also measured. Results: The angle between the mandibular first premolar axis and buccal cortex, the distance between the root apex and buccal cortex, angle of vestibularization, arc of vestibularization, and root apex maximum movable distance were significantly greater in the short face type than in the long and norm face types. The angle between the mandibular second premolar axis and buccal cortex, the distance from root apex to buccal cortex, and the arc of vestibularization were significantly greater in the short face type than in the normal face type. Conclusions: There are significant differences in the mandibular premolar positions in Class I subjects according to vertical facial type.

• 대한장애인치과학회지
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• 제13권1호
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• pp.43-46
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• 2017

본 증례는 함입 주소로 내원한 9세 4개월 뇌성마비 남환을 미다졸람 근주를 이용한 의식하 진정법으로 해당치아의 수술 적 재위치 및 근관치료를 시행하였다. 5년이 지난 현재 유착 소견 및 부분적인 치근흡수가 보이나 양호한 상태로 유지되고 있다. 뇌성마비 환자의 경우 치아 및 주위조직에 취약하며, 치료 시 적절한 행동조절 및 치료 방법을 선택하는 임상의의 노력이 필요하다.

• International Journal of Oral Biology
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• 제34권2호
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• pp.53-59
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• 2009

Periodontal ligament (PDL) tissue is a connective tissue that is interposed between the roots of the teeth and the inner wall of the alveolar bone socket. PDL is always exposed to physiologic mechanical force such as masticatory force and PDL cells play important roles during orthodontic tooth movement by synthesizing and secreting different mediators involved in bone remodeling. The Wnt/${\beta}$-catenin signaling pathway was recently shown to play a significant role in the control of bone formation. In the present study, we applied cyclic tensile stress of 20% elongation to cultured human PDL cells and assessed its impact after six days upon components of the Wnt/${\beta}$-catenin signaling pathway. RTPCR analysis showed that Wnt1a, Wnt3a, Wnt10b and the Wnt receptor LRP5 were down-regulated, whereas the Wnt inhibitor DKK1 was up-regulated in response to these stress conditions. In contrast, little change was detected in the mRNA expression of Wnt5a, Wnt7b, Fz1, and LRP6. By western blotting we found decreased expression of the ${\beta}$-catenin and p-GSK-3${\beta}$ proteins. Our results thus show that mechanical stress suppresses the canonical Wnt/${\beta}$-catenin signaling pathway in PDL cells.

• Imaging Science in Dentistry
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• 제42권2호
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• pp.83-88
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• 2012

Purpose : The aim of this study was to investigate the initial effects of maxillary expansion therapy with Hyrax appliance and to evaluate the related changes in maxillary sinus volume. Materials and Methods : Thirty patients (20 females, 10 males; 13.8 years) requiring maxillary expansion therapy, as part of their comprehensive orthodontic treatment, were examined. Each patient had cone-beam computed tomography (CBCT) images taken before (T1) and after (T2) maxillary expansion therapy with a banded Hyrax appliance. Multiplanar slices were used to measure linear dimensions and palatal vault angle. Volumetric analysis was used to measure maxillary sinus volumes. Student t tests were used to compare the pre- and post-treatment measurements. Additionally, differences between two age groups were compared with Mann-Whitney U test. The level of significance was set at p=0.05. Results : Comparison of pre-treatment to post-treatment variables revealed significant changes in the transverse dimension related to both maxillary skeletal and dental structures and palatal vault angle, resulting in a widened palatal vault (p<0.05). Hard palate showed no significant movement in the vertical and anteroposterior planes. Nasal cavity width increased on a mean value of 0.93mm(SD=0.23, p<0.05). Maxillary sinus volume remained virtually stable. No significant age differences were observed in the sample. Conclusion : Hyrax expansion therapy did not have a significant impact on maxillary sinus volume.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제33권2호
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• pp.109-113
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• 2007

Introduction. In patients with mandibular prognathism, Bilateral Sagittal Split Ramus Osteotomy(BSSRO) combined with orthodontic treatment reduces oral volume and influences tongue and other surrounding tissues. Purpose of this study was to analyze post-operative tongue position and airway dimension, as well as mandibular changes in vertical, horizontal, and angular dimensions. Materials and methods. Height of dorsum of tongue, width of airway, gonial angle and lower facial height of mandibular prognathic patients who visited Kangdong Sacred Heart Hospital from Jan. 2001 to Dec. 2006 were anaylzed via pre-operative and post-operative cephalograms. T-test was used to compare pre-operative and post-operative measurements. Also, correlations among pre-operative measurements of the patients were analyzed. Results and conclusion. A significant correlation was shown between ANS-Xi-PM area and location of dorsum of tongue in pre-operative patients. A significant superior movement of tongue and decrease of airway width was observed in post-operative patients. Also the upper gonial angle decreased significantly.

• 구강회복응용과학지
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• 제30권4호
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• pp.329-338
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• 2014

치주질환이나 우식으로 인해 구치부 치아가 상실된 환자들은 잔존하고 있는 전치부 및 소구치부 치아로 안정된 교합고경을 유지하기 어렵다. 구치의 상실로 대합치의 정출이나 인접치의 경사가 발생되는 경우 교합평면이 붕괴되거나 부적절한 교합간섭을 야기하게 된다. 만약 치아 상실 상태가 지속된 경우에는 하악의 전방이동으로 인해 상악 전치의 동요와 순측 이개를 초래하게 되며 치주질환이 동반된 경우에는 더욱 심각한 상황으로 변화한다. 이와 같이 치아의 병적 이동이 일어난 환자의 치료는 보존 및 치주치료, 교정 치료를 통한 재배열, 그리고 상실된 치아의 보철수복을 통한 교합 고경의 재설정 및 유지와 같은 다과간 협력 진료가 매우 중요하다.

• 대한치과교정학회지
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• 제36권6호
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• pp.465-473
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• 2006

교정적 치아이동과 밀접한 관련이 있는 치주인대세포에서, 산화질소가 세포의 증식과 분화에 미치는 영향을 알아보고자 하였다. 인간 치주인대세포를 분주한 후에 산화질소의 donor인 SNP의 농도에 따라 실험군을 구분하고, 세포 활성 염기성 인산분해효소 활성, Western blot 분석을 통한 osteonectin과 bone sialoprotein의 발현 정도를 측정하였다. 0.2 mM 이하의 저농도 SNP를 처리한 실험군에서 대조군과 비교하여 세포 활성, 염기성 인산분해 효소의 활성, 그리고 osteonectin과 bone sialoprotein의 발현이 유의하게 증가하였다. 그러나 1 mM 이상의 고농도 SNP를 처리한 실험군에서는 오히려 감소하였다. 산화질소는 인간 치주인대세포에서 저농도는 세포의 증식과 분화에 촉진 효과를, 고농도는 억제 효과를 보이는 biphasic effect를 갖는다.

• 대한소아치과학회지
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• 제27권4호
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• pp.479-484
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• 2000

III급 부정교합, 특히 전치부 반대 교합은 부모나 주위 사람에 의해 쉽게 인지되기 때문에 비교적 어린 시기에 내원하는 빈도가 높아지고 있다. 이에 따라 치과의사는 치료시기에 대한 결정, 적절한 case의 선택, 장기간에 걸친 치료, 치료후의 재발 등에 대한 심리적 부담감을 안게 되며 보호자 또한 시간적, 경제적인 어려움을 겪게 된다. 그러나, 반대 교합 그 자체는 조기 개선시 상악골의 성장 저해를 막을 수 있으며, 하악 과성장을 억제함으로써 기능성 인 경우에 골격성으로의 발전을 억제 할 수 있다. 그리고 상하악골의 골격 부조화가 매우 크거나 좋은 예후를 기대하기 힘든 골격 구조에 대해서도 정확한 평가가 병행 되어야 한다. 골격성 III급 부정교합으로 내원한 환아를 성장기 동안 치료함으로써 다음과 같은 결론을 얻었다. 1. 상악골의 정상적 인 성장 저해 요소를 제거하고, 하악골의 과성장을 조절해줌으로써 전치부 반대교합을 해소하였다. 2. 상악골과 상악 전치는 전하방으로, 하악골과 하악 전치는 후하방으로 이동하였다. 3. 경조직, 연조직의 변화로 인해 안모의 개선을 나타내었다.

• 대한치과교정학회지
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• 제43권1호
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• pp.42-52
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• 2013

The aim of this paper was to propose a new method of bimaxillary orthognathic surgery planning and model surgery based on the concept of 6 degrees of freedom (DOF). A 22-year-old man with Class III malocclusion was referred to our clinic with complaints of facial deformity and chewing difficulty. To correct a prognathic mandible, facial asymmetry, flat occlusal plane angle, labioversion of the maxillary central incisors, and concavity of the facial profile, bimaxillary orthognathic surgery was planned. After preoperative orthodontic treatment, surgical planning based on the concept of 6 DOF was performed on a surgical treatment objective drawing, and a Jeon's model surgery chart (JMSC) was prepared. Model surgery was performed with Jeon's orthognathic surgery simulator (JOSS) using the JMSC, and an interim wafer was fabricated. Le Fort I osteotomy, bilateral sagittal split ramus osteotomy, and malar augmentation were performed. The patient received lateral cephalometric and posteroanterior cephalometric analysis in postretention for 1 year. The follow-up results were determined to be satisfactory, and skeletal relapse did not occur after 1.5 years of surgery. When maxillary and mandibular models are considered as rigid bodies, and their state of motion is described in a quantitative manner based on 6 DOF, sharing of exact information on locational movement in 3-dimensional space is possible. The use of JMSC and JOSS will actualize accurate communication and performance of model surgery among clinicians based on objective measurements.

• 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.