• 대한치과교정학회지
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• 제49권5호
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• pp.279-285
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• 2019

Objective: This study evaluated the efficiency of anchorage provided by temporary anchorage devices (TADs) in maxillary bicuspid extraction cases during retraction of the anterior teeth using a fixed appliance. Methods: Patients aged 12 to 50 years with malocclusion for which bilateral first or second maxillary bicuspid extractions were indicated were included in the study and randomly allocated to the TAD or control groups. Retraction of the anterior teeth was achieved using skeletal anchorage in the TAD group and conventional dental anchorage in the control group. A computed tomography (CT) scan was performed after alignment of teeth, and a second CT scan was performed at the end of extraction space closure in both groups. A three-dimensional superimposition was performed to visualize and quantify the maxillary first molar movement during the retraction phase, which was the primary outcome, and the stability of TAD movement, which served as the secondary outcome. Results: Thirty-four patients (17 in each group) underwent the final analysis. The two groups showed a significant difference in the movement of the first maxillary molars, with less significant anchorage loss in the TAD group than that in the control group. In addition, TAD movement showed only a slight mesial movement on the labial side. On the palatal side, the mesial TAD movement was greater. Conclusions: In comparison with conventional dental anchorage, TADs can be considered an efficient source of anchorage during retraction of maxillary anterior teeth. TADs remain stable when correctly placed in the bone during the anterior tooth retraction phase.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제29권4호
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• pp.245-248
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• 2003

The retraction of anterior teeth could be performed more easier by inducing of skeletal anchorage system rather than by conventional method on orthodontic treatment. But, we wonder how effective the system draws well without anchorage loss and draws anterior teeth aside posteriorly, and if the system can reduce the time, in comparison with the anchorage of posterior teeth. For that reason we have studied on the subject of patients, who were required the maximum anchorage on orthodontic treatment and the cases without crowding. The subjects of the experimental group are 35 areas of 20 people who were inserted miniscrews after Mx or Mn 1st premolar extracted. Also, the subjects of the control group are 81 areas of 45 people who were not inserted miniscrews. Compared the anchorage loss of experimental group with control one, we could get the result that the anchorage loss of experimental group is $1.034{\pm}0.891mm$ and control group is $2.790{\pm}1.882mm$(P<0.01). Compared the space closing time of experimental group with control one, we could get the result that the space closing time of experimental group is $369.40{\pm}110.81$days and control group is $406.56{\pm}231.63$days. But the result of comparing space closing time has no significance in statistics. We recognized that the experimental group is more faster than the control group in the canine retraction velocity from the result ; the speed of a experimental group has as much as $0.60{\pm}0.23mm/30days$ while the speed of a control group has $0.44{\pm}0.35mm/30days$(P<0.05). So, we could convince that orthodontic miniscrew is used effectively in the cases required the maximum anchorage.

• 대한치과교정학회지
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• 제34권2호
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• pp.197-203
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• 2004

골격성 II급 부정교합을 치료하는데 있어서, Tweed-Merrifield directional force technology는 시계 반대 방향으로의 양호한 골격적 변화 및 균형 잡힌 안모를 얻는데 기여하고 있다. 이는 적절한 방향으로의 J-hook을 통한 headgear force의 사용이 필수적이다. 따라서 환자의 협조에 대한 의존이 절대적이므로 약간의 문제점이 있는 것 또한 사실이다. 하지만 최근 skeletal anchorage를 이용하여 환자의 협조를 최소화하면서도 보다 효과적으로 고정원 보강을 할 수 있는 방법이 많이 시행되고 있어 이를 보완 할 수 있게 되었다. 저자는 HPJH(high pull J-hook)과 skeletal anchorage를 병용하여 directional force를 적용한 결과 상악 구치부에서의 고정원 보강과 상악 전치부의 토크 조절 및 mandibular response를 얻음으로써 양호한 안모의 균형을 얻을 수가 있었다. 이 치료 결과로 보아 skeletal anchorage는 HPJH을 대신하여 상악 견치 및 전치부 견인시 상악 구치부의 전후적 및 수직적 고정원 보강 역할을 할 수 있을 것으로 생각된다 상악 전치부 견인시 상악 전치부의 토크 조절, 압하 및 치체이동을 위해 HPJH을 사용하였지만, 이 또한 mini 혹은 microscrew로 대체한다면 환자의 협조를 최소화하면서도 양호한 치료결과를 얻을 수 있을 것으로 생각된다.

• Smart Structures and Systems
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• 제21권4호
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• pp.421-433
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• 2018

Carbon fiber reinforced polymer (CFRP) cable has good mechanical properties and corrosion resistance. However, the anchorage of CFRP cable is a big issue due to the anisotropic property of CFRP material. In this article, a high-efficient bonding anchorage with novel configuration is developed for CFRP cables. The acoustic emission (AE) technique is employed to evaluate the performance of anchorage in the fatigue test and post-fatigue ultimate bearing capacity test. The obtained AE signals are analyzed by using a combination of unsupervised K-means clustering and supervised K-nearest neighbor classification (K-NN) for quantifying the performance of the anchorage and damage evolutions. An AE feature vector (including both frequency and energy characteristics of AE signal) for clustering analysis is proposed and the under-sampling approaches are employed to regress the influence of the imbalanced classes distribution in AE dataset for improving clustering quality. The results indicate that four classes exist in AE dataset, which correspond to the shear deformation of potting compound, matrix cracking, fiber-matrix debonding and fiber fracture in CFRP bars. The AE intensity released by the deformation of potting compound is very slight during the whole loading process and no obvious premature damage observed in CFRP bars aroused by anchorage effect at relative low stress level, indicating the anchorage configuration in this study is reliable.

• 대한치과의사협회지
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• 제52권9호
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• pp.532-540
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• 2014

In contemporary orthodontic treatment skeletal temporary anchorage devices (TADs) are routinely used as an anchorage reinforcement to provide improved anchorage control with reduced requirement for patient's compliance. For past few decades, various types of TADs have been explored and their clinical application has been expanded. Therefore, the purpose of this article is to present three major types of orthodontic skeletal anchorage devices and discuss their rationale, clinical procedure, insertion site, and potential complications as well as their management.

• 대한치과교정학회지
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• 제31권4호
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• pp.415-424
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• 2001

교정치료에 있어서 anchorage는 진단 및 치료계획에서부터 치료 종료 단계까지 교정의사가 항상 염두에 두면서 치료를 진행 해야 하는 중요한 요소이다. 환자의 적극적인 협조를 필요로 하는 전통적인 anchorage 조절법 보다는 miniscrew 같은 skeletal anchorage 가 좀더 효과적인 방법으로 제시되어 지고 있어, miniscrew의 교정적 이용 시 고려사항에 대하여 전반적인 고찰과 증례보고를 통해서 niniscrew의 다양한 임상적 적용에 대해서 살펴보았다. 또한 midpalate부위가 miniscrew의 식립 부위로서 가지는 장점과 식립 시의 주의사항을 알아보았으며 skeletal anchorage 가 교정에 도입되면서 치료개념과 방법에 있어서의 변화를 요약하면 다음과 같다. 1. 절대적인 개념의 Anchorage가 도입 되었다. 2. 생역학적 면에서 치아의 치체이동이 쉬워지고 determinate system이 설계되어 질수 있다. 3. 기존의 수술로만 가능했던 치료들 중 일부는 교정 치료만으로 치료가 가능하게 되었다.

• 대한치과교정학회지
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• 제34권5호
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• pp.458-464
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• 2004

교정치료에 있어서 고정원의 조절은 매우 중요한 요소이며, 상악에서 특히 그러하다. 이를 얻기 위해 많은 노력을 해 왔으나 대부분이 환자의 협조에 대한 의존이 필수적이었기 때문에 고정원 보강에 대하여 확신할 수 없었다. 하지만 최근 skeletal anchorage를 이용하여 환자의 협조를 최소화하면서도 보다 효과적으로 고정원 보강을 할 수 있는 방법이 시행되고 있다. 또한 과거의 골 융합성 임프란트와 달리 미니 스크류는 구강 내의 어느 부위에나 식립할 수 있을 정도로 식립 부위의 제한성이 적다는 장점이 있다. 저자는 titanium miniscrew를 구개 정중부의 약간 측방에 식립하고, indirect active P.S.A.(Palatal skeletal anchorage)를 이용하여 치료한 결과 상악 구치부에서의 고정원 보강을 얻을 수가 있었다. 이 치료 결과로 보아 PSA는 상악 구치부의 고정원 보강 역할을 할 수 있을 것으로 생각되며. 또한 transpalatal arch system의 다양한 design을 응용한다면 효율적인 치아 이동을 하는데 많은 도움이 될 것으로 생각된다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제28권4호
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• pp.249-255
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• 2002

Recently, Skeletal Anchorage System (SAS) has been focused clinically with the view point that it could provide the absolute intraoral anchorage. First, it began to be used for the patient of orthognathic surgery who had difficulty in taking intermaxillary fixation due to multiple loss of teeth. And then, its uses have been extended to many cases, the control of bone segments after orthognathic surgery, stable anchorage in orthodontic treatment, and anchorage for temporary prosthesis and so on. SAS has been developed as dental implants technique has been developed and also called in several names; mini-screw anchorage, micro-screw anchorage, mini-implant anchorage, micro-implant anchorage (MIA), and orthosystem implant etc. Now many clinicians use SAS, but the anatomical knowledges for the installed depth of intraosseous screws are totally dependent on general experiences. So we try to study for the cortical thickness of maxilla and mandible in Korean adults without any pathologic conditions with the use of Computed Tomography at the representative sites for the screw installation.

• 대한치과교정학회지
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• 제28권2호
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• pp.269-276
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• 1998

마찰견인법으로 상악견치를 후방견인할 때, 저항원상실을 최소로 하며 조절되지못한 경사이동을 예방하기 위한 장치인 MAS(molar anchoring spring)를 고안하여 임상에 적용하였다. 31명(여자 29명, 남자 2명)의 표본에서 MAS를 사용하여 상악견치의 후방견인을 시행하였고, 견인 전후의 측모 두부 방사선 규격사진, orthopantomogram과 치아모형을 채득하였다. 얻어진 정보로부터 상악 제1대구치의 저항원소실 및 상악 견치의 경사이동경향을 조사하여 다음과 같은 결과를 얻었다. 1. 상악 제1대구치의 경우 수직정출과 jntermolar width의 변화가 없었으며, 시상면에서 적은 양의 저항원소실만이 있었다. 2. 상악 견치의 경우 원심경사 및 약간의 압하가 일어났으며 교합이 깊어졌다는 소견은 보이지 않았다.

• 한국공간구조학회논문집
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• 제19권1호
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• pp.45-51
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• 2019

In this study, the static load test and the load transfer test were carried out to evaluate the structural performance of the circular anchorage proposed by the previous study. Specimens were fabricated according to KCI-PS101 and ETAG 013. As a result of the static load test, it was verified that the displacement of the wedge and the strand was kept constant when the tensile force of 80% of the nominal strength of the strand was applied. In the load transfer test, it was confirmed that all the specimens satisfied the stabilization formula of KCI-PS101 and ETAG 013. Post-tensioned one-way slab with circular anchorage were fabricated to evaluate the flexural behavior. All specimens exhibited the same flexural behavior and maximum load. However, the specimen with circular anchorage were advantageous than the rectangular anchorage one in terms of crack control of the anchorage zone.