• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제29권2호
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• pp.102-107
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• 2003

At orthodontic treatment, we have made every effort to get rigid anchorage which is not stirred when teeth move. As a result, the miniscrew that is rigid anchorage was invented recently, and now it is used widely. Concerning the advantage of miniscrew, it is reduced dependence of extraoral anchorage and it shortens treatment time for rapid tooth movement. In contrast, the defect of miniscrew is falling off it resulted from increasing of the mobility. So the purpose of this research is to be of help to prognose clinical use of miniscrew, which is inserted for intraoral anchorage, by investigating and comparing the failure rate of miniscrew for loading time. This study researches the failure rate of miniscrew for teeth movement at the orthodontic treatment. The failure rate of miniscrew in mid course, after inserting 147 miniscrews in 51 patients, is 13%(20/147). It showed no statistically significant differences as compared man with woman, maxilla with mandible, double-head with uni-head miniscrew, and drilling and non-drilling before inserting the miniscrew. In comparison below twenties with over twenties and the times that we give load to miniscrew, it produced that the failure rate of miniscrew is 9.7% higher in the case of below the twenties than over the twenties. Also, the failure rate of loading immediately is 10.8% higher than loading after 7 days. According to using driver for the insertion of miniscrew, the failure rate of miniscrew is higher in the case of using machined driver than in the case of using hand driver when the level of significance is 95%. According to the research, we can suppose that the failure rate has no concern with using miniscrew on man or woman, maxilla or mandible, the shape of head, and drilling or non-drilling before insertion of miniscrew. Therefore, we can choose eclectic miniscrew as demands. In addition, we must notify the patient, below twenties, to be possibility of high failure rate. And It is strongly recommended to give load after $1{\sim}2$ weeks for healing of the insertion area.

• 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.

• 대한치과보철학회지
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• 제45권4호
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• pp.492-505
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• 2007

Statement of problem: An orthodontic miniscrew implant has been used as a skeletal anchorage for orthodontic treatment. However, any relation among the influence of the cortical bone, morphologic differences of orthodontic miniscrew implants and new bone formation hasn't been made clear yet. Purpose: The purpose of this study was to evaluate whether the orthodontic miniscrew implant could work as an intraoral skeletal anchorage immediately and stably for orthodontic treatment after insertion of it. Material and methods: Two types of orthodontic miniscrew implants were used in this experiment; tapered type and straight type. One hundred and sixty eight orthodontic miniscrew implants were inserted into the tibiae of 21 rabbits and sacrificed on 3, 7, 11, 14, 21 and 28days later after insertion of them to study removal torque values and histologic and histomorphometric analyses. Results: The results were as follows. 1. The removal torque values of the tapered type were higher than those of the straight type in all groups(p<0.05). 2. There wasn't any distinguishing differences between the tapered type and the straight type about the new bone formation percentage. 3. The removal torque values for both the tapered type and the straight type were gradually decreased at early stages of the test but started to increase at the 7 days group of the straight type and the 11 days group of the tapered type. 4. New bone formation percentage was increased gradually for both the tapered and the straight types as time passed(p<0.05). 5. It was found that the tapered type showed lower values in the cortical bone about both the maximum equilibratory stress distribution and the maximum principal stress distribution than the straight type in linear finite elements analysis. Conclusion: According to the research, the removal torque values were decreased at 7 days group of the tapered type and 11 days group of the straight type after the insertion of the orthodontic miniscrew implants in tibiae of rabbits. Considering the human bone activity, it is better to apply the orthodontic force $3{\sim}4$ weeks later than to apply it immediately after the insertion of orthodontic miniscrew implants. Considering that general orthodontic force is about $250{\sim}500$ grams, the tapered type can be worked as a stable skeletal anchor age in an orthodontic treatment even if the orthodontic force is applied on it immediately after the insertion of it.

• 대한기계학회논문집A
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• 제28권8호
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• pp.1237-1244
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• 2004

The orthodontic surgery including lingual orthodontics has recently attracted a person's attention due to its functional and esthetic appreciation. The skeletal anchorage with the miniscrew is newly adopted in the lingual orthodontics to assist the upholding ability. The appliciation needs to understand the mechanism of the orthodontic appliance and its related orthodontic correction for optimal orthodontic treatment. There is, however, few information about the qualitative and quantitative effect of the orthodontic appliance with the miniscrew has not been well identified. In this paper, three dimensional finite element analysis is introduced to the lingual orthodontics in order to investigate the effect of the anterior retraction force on the miniscrew and transpalatal arch wire. The analysis determines the adequate location of the miniscrew and the point of force application of the anchorage system in the lingual orthodontics. The analysis results demonstrate the effect of the position of the miniscrew and the transpalatal arch wire on the lingual orthodontics.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.198-203
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• 2004

In these days, the orthodontic surgery including lingual orthodontics has attracted a person' attention due to its functional and esthetic appreciation. The delivery of the optimal orthodontic treatment is greatly influenced by clinician' ability to predict and control the tooth movement by applying force system to dentition. The skeletal anchorage system with the miniscrew has been used recently in the lingual orthodontics to assist the anchorage control. Precise understanding of the force system produced from the various orthodontic appliances is necessary. However, the qualitative and quantitative effect of the miniscrew has not been identified well. In this paper, three dimensional finite element analysis is introduced on the lingual orthodontics to investigate the effect of anterior retraction force on the miniscrew and transpalatal arch wire. The purpose of this study is to determine the location of the miniscrew and the point of force application of the anchorage system in the lingual orthodontics. The analysis results indicate the efficient position of the miniscrew and the transpalatal arch wire in the lingual orthodontics.

• 대한소아치과학회지
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• 제35권2호
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• pp.367-375
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• 2008

교정치료 시 고정원은 항상 염두에 두면서 치료를 진행해야 하는 중요한 요소이다. 전통적인 고정원을 이용한 치료는 환자의 적극적인 협조를 필요로 하고 원하는 치아이동에 대한 반작용이 나타날 수 있는 등의 부작용을 가지고 있다. 그러므로 보다 견고한 구강 내 고정원이 요구되어져 왔으며 이를 위해 miniscrew가 임상에서 흔히 이용되고 있다. Miniscrew를 통한 고정원의 확보는 구외력 의존도 감소, 치료기간의 단축, 식립 후 즉시 교정력 적용, 환자의 협조도 불필요, 식립의 간편성, 저렴한 비용 등의 장점을 가지고 있다. 그러나 성장기 환자는 성인에 비해 골질이 좋지 않아 miniscrew의 성공률이 성인에 비해 낮다. 그러나 일단 고정에 성공하면 많은 교정치료 시 매우 유용하게 이용할 수 있다. 본 증례는 혼합치열기 환자를 miniscrew를 이용하여 정중이개 및 정중선 불일치, 매복치에 대한 양호한 교정치료를 하였기에 보고하는 바이다.

• 대한소아치과학회지
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• 제37권4호
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• pp.537-544
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• 2010

교정치료에 있어서 고정원은 진단 및 치료계획에서부터 치료 종료 단계까지 항상 염두에 두어야 하는 중요한 요소이다. 전통적으로 고정원의 조절을 위하여 차등력, 차등모멘트, 구내 고정원, 구외 고정원 등의 다양한 방법들이 사용되어져 왔다. 그러나 이러한 방법들은 원치 않는 치아의 이동이 발생할 수 있고 환자의 협조도가 필요하다는 한계가 있다. 따라서 환자의 협조도나 주변 치아에 의존하지 않는 골격성 고정원(skeletal anchorage)이 전통적인 방법들의 단점을 극복할 수 있는 대안으로 제시되었다. 골격성 고정원의 종류로는 implant, onplant, miniplate, miniscrew 등이 있다. 이 중에서 miniscrew는 환자의 협조도 감소, 술식의 간편성, 저렴한 비용, 식립부위의 다양성 등의 장점을 가지고 있어 교정치료 시 유용하게 이용될 수 있다. 본 증례는 이소성 맹출 경로를 보이는 상악 견치와 매복된 하악 견치의 견인, 정출된 상악 전치의 압하에 miniscrew를 이용하여 양호한 결과를 보였기에 보고하는 바이다.

• 대한치과교정학회:학술대회논문집
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• 대한치과교정학회 2001년도 제34회 학술대회
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• pp.81.1-81.1
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• 2001

• 대한치과교정학회지
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• 제41권1호
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• pp.36-41
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• 2011

Objective: The aim of this study was to measure tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) levels around miniscrews used for anchorage during a 3-month period of canine distalization. Methods: Sixteen patients (8 boys, 8 girls; mean age, $16.6{\pm}2.4$ years) whose upper first premolars were extracted for orthodontic treatment were included in this study. Miniscrews were used as an anchorage unit in canine distalization. Thirty-two (32) miniscrew implants were placed bilaterally in the alveolar bone between the maxillary second premolars and first molars. The treatment, miniscrew, and control groups comprised upper canines, miniscrew implants, and upper first premolars, respectively. Peri-miniscrew implant crevicular fluid and gingival crevicular fluid were obtained before applying force and at 1, 24, and 48 hours, and at 7 and 21 days, and 3 months after applying force. Results: During the 3-month period, the (TNF-${\alpha}$) levels increased significantly at 24 hours only in the treatment group (p < 0.01). In the miniscrew and control groups, there were no statistically Significant changes. No significant differences were observed between groups. Conclusions: Miniscrews can be conveniently used for anchorage in orthodontics.

• 대한치과교정학회지
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• 제46권4호
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• pp.189-198
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• 2016

Objective: The purpose of this study was to analyze stress distributions in the roots, periodontal ligaments (PDLs), and bones around cylindrical and tapered miniscrews inserted at different angles using a finite element analysis. Methods: We created a three-dimensional (3D) maxilla model of a dentition with extracted first premolars and used 2 types of miniscrews (tapered and cylindrical) with 1.45-mm diameters and 8-mm lengths. The miniscrews were inserted at $30^{\circ}$, $60^{\circ}$, and $90^{\circ}$ angles with respect to the bone surface. A simulated horizontal orthodontic force of 2 N was applied to the miniscrew heads. Then, the stress distributions, magnitudes during miniscrew placement, and force applications were analyzed with a 3D finite element analysis. Results: Stresses were primarily absorbed by cortical bone. Moreover, very little stress was transmitted to the roots, PDLs, and cancellous bone. During cylindrical miniscrew insertion, the maximum von Mises stress increased as insertion angle decreased. Tapered miniscrews exhibited greater maximum von Mises stress than cylindrical miniscrews. During force application, maximum von Mises stresses increased in both groups as insertion angles decreased. Conclusions: For both cylindrical and tapered miniscrew designs, placement as perpendicular to the bone surface as possible is recommended to reduce stress in the surrounding bone.