• Title/Summary/Keyword: 힘교정

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PHYSICAL PROPERTIES OF VAR10US BRANDS OF ELASTOMERIC CHAINS (수종의 합성 고무탄성재의 성질에 관한 연구)

  • Kim, Kyung-Ho;Hwang, Chung-Ju;Sung, Sang-Jin
    • The korean journal of orthodontics
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    • v.27 no.6 s.65
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    • pp.943-954
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    • 1997
  • Forces needed for orthodontic tooth movement are obtained from various appliances such as orthodontic wires or elastic rubber. Orthodontic elastic rubber is widely used clinically, but permanent deformation and force decay may occur from the environmental changes, time of clinical use and the extent of the stretch, making the Prediction of force being applied difficult. The Present study examined and compared the changes in residual force between three brands of elastomeric chains (Ormco Generation II Power Chains ; brand A, RMO : Energy-Chain ; brand B, Unitek : AlastiK ; brand C) under various environmental conditions, amount of initial force, types of elastomer and the rate of extension. The characteristic physical properies of the elastomeric chains were as follows. 1. In all three brands, the residual force ratio was largest when the chains were stored in air, with no difference between water and saliva. 2. In all three brands, after 24 hours, there was no statistical difference in residual force ratio according to the initial force level. 3. In Brand A and B, the presence of filament had no correlation with the residual force ratio. In Brand C force decay was more severe when the chain contained filament. 4. In each brand, rate of extension had no effect on residual force ratio. 5. Brand B showed relatively higher residual force ratio compared to other brands.

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BUILD-UP 원리를 이용한 힘센서 제작 및 특성평가에 관한 연구

  • ;Force Lab
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2001.10a
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    • pp.154-158
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    • 2001
  • 산업이 고도화, 대형화됨에 따라 조선, 건설, 기계산업문야에서 대용량 힘 측정의 필요성이 날로 증가하고 있다. 힘 측정에 사용되는 힘 센서는 국가 힘 표준인 힘 표준기로부터 교정을 받아 사용함으로써 힘 측정 결과에 대해 국제적으로 인정받을 수 있다. 본 연구에서는 build-up 힘 표준기에 사용되는 build-up 힘센서를 설계 및 제작하고 힘 센서 각각의 특성과 build-up 시스템 전체의 특성을 실험하여 build-up 힘 센서의 오차를 평가하였다.

Intercomparison of Force Standards between Korea and Germany (한 . 독 힘 표준 국제비교)

  • ;;A. Sawla
    • Journal of the Korean Society for Precision Engineering
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    • v.11 no.2
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    • pp.141-148
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    • 1994
  • 국가간에 힘 측정 또는 힘 측정기기의 교정 결과에 대한 상호 신뢰를 확보하기 위해서는 힘 표준에 대한 상호비교가 필수적이다. 본 논문에서는 한국의 힘 표준에 대한 국제적 신뢰를 확보하기 위하여 세계 여러 나라들과 힘 표준에 대한 국제비교 연구를 수행한 독일연방물리청과 힘 표준의 상호비교를 실시하였다. 비교시험 결과 한국과 독일의 힘 표준의 상대 편차는 100 kN .approx. 500 kN벙위에서 .+-. 5.5*$10^{-5}$ 이내로 나타났으며, 한국의 힘 표준의 정확도가 국제적 수준임을 확인하였다.

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A BIOMECHANICAL STUDY ON THE EFFECT OF LIGHT WIRE TORQUING AUXILIARY (Light wire torquing auxiliary의 효용도에 관한 생력학적 연구)

  • Park, Kyung Jin
    • The korean journal of orthodontics
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    • v.2 no.1
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    • pp.29-34
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    • 1971
  • 저자는 교정환자 치료에 흔히 사용되는 Light wire torquing auxiliary의 반경의 크기 및 교합면에 대한 spur 각도의 증감에 따라 Light wire torquing auxiliary 애서 발생되는 힘이 어떻게 변화하는 가를 Dentiform typodont 위에서 측정 관찰하여 아래와 같은 결과를 얻었다. 1) Light wire torquing auxiliary circle의 반경의 크기가 감소할 수록 발생되는 힘의 크기는 증가하였으나, 반경의 크기에 반비례하지는 않았다. 즉, Light wire torquing auxiliary circle의 반경을 20 mm.에서 10mm.로 하였을때 발생되는 force는 2배로 나타나지는 않았다. 2) 교합 평면에 대한 spur의 각도가 감소할 수록 force는 증가하였다. 이때 교합 평면에 대한 spur의 각도를 감소시킨 상태에서 교합 평면과 치아가 이루는 각도를 증가시켜 줌으로써 항속적인 힘의 증가를 나타냈다.

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Intrusion of the extruded maxillary central incisor using skeletal anchorage system and unilateral segmental intrusion arch (골성 고정원과 편측 분절호선을 이용한 정출된 상악 중절치의 압하 치료)

  • Kwon, Eun-Young;Baek, Young-Jae;Park, Soo-Byung;Kim, Seong-sik;Kim, Yong-il;Choi, Youn-kyung
    • Journal of Dental Rehabilitation and Applied Science
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    • v.35 no.3
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    • pp.180-190
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    • 2019
  • Patients who have a moderate periodontitis with pathologic tooth migration of maxillary incisors, it is necessary not only periodontal treatment for reduce periodontal inflammation, but also orthodontic treatment to teeth repositioning. For orthodontic treatment, it is necessary to apply less force and careful considerations of the center of resistance of the tooth and optimal force of tooth movement. At this time, the segmental arch applied only to the target teeth, is more effective and predictable, because applied force and direction can be controlled. In addition, to design the orthodontic appliance that can prevent the unwanted tooth movement that used as an anchorage is important. In recent years, various types of skeletal anchorage system have been used for preventing loss of the anchorage. We reported the patient who had extruded maxillary central incisor due to pathologic tooth migration, treated by a successful periodontal-orthodontic multidisciplinary treatment using an orthodontic appliance designed to apply less traumatic force and reduce an anchorage loss.

Development of Calibration System for Multi-Axis Force/Moment Sensor and Its Uncertainty Evaluation (다축 힘/모멘트 센서 교정기의 개발 및 그의 불확도 평가)

  • Kim, Gab-Soon;Yoon, Jung-Won
    • Journal of the Korean Society for Precision Engineering
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    • v.24 no.10
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    • pp.91-98
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    • 2007
  • This paper describes the development of the calibration system for a multi-axis force/moment sensor and its uncertainty evaluation. This calibration system can generate the continuous forces (${\pm}Fx,\;{\pm}Fy$ and ${\pm}Fz$) and moments (${\pm}Mx,\;{\pm}My$ and ${\pm}Mz$). Many kinds of multi-axis force/moment sensors in industries should be carried out the characteristic test or the calibration with the calibration system that can generate the forces and the moments. The calibration systems have been already developed are the disadvantages of the low capacity, the generation of step forces(10N, 20N ...) and step moments(1Nm, 2Nm ...) with weights, the high coasts in manufacture and so on. In this paper, the calibration system for a multi-axis force/moment sensor that can generate the continuous three forces and three moments was developed. Their ranges are $0{\sim}2000N$ in all force-directions and $0{\sim}400Nm$ in all moment-directions. And the system was evaluated in the expanded relative uncertainty. They were ${\pm}0.0004$ in all forces ${\pm}Fx,\;{\pm}Fy$ and ${\pm}Fz$, and ${\pm}0.0004$ in all moments ${\pm}Mx,\;{\pm}My$ and ${\pm}Mz$.

A SOFT X-RAY STUDY ON THE BONE REMODELLING IN TOOTH MOVEMENT OF DOG (성견의 실험적 치아이동시 골재형성에 관한 연X선학적 연구)

  • Kim, Sang-Cheol
    • The korean journal of orthodontics
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    • v.25 no.5 s.52
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    • pp.587-592
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    • 1995
  • The purpose of this study was to observe the pattern of bone remodellings in the periodontal ligament of dog, in which experimental tooth movement was performed A control and 5 experimental dogs, one and half year in age, were studied. Light force (50-75g) was applied by placing open-coil spring between left mandibular premolars ; heavy force (250-300g), between right mandibular premolars. Experimental dogs were sacrificed at 12 hours, 1, 3 ,7 and 14 days after force application, respectively. And soft X-ray films were obtained and read on the sectioned periodontal tissue around mandibular premolars. The results were as follows. 1. New bone formation began to be observed in tension side at 7-day and increased at 14-day , No difference was observed between light force group and heavy force group. 2. Bone resorption was observed as a shape of destruction of lamina dura at 3-day and increased gradually at 7-day, 14-day.

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What Is Nano-Force Metrology? (나노 힘이란 무엇인가?)

  • 김민석;최인묵;박연규;김종호;강대임
    • Journal of the Korean Society for Precision Engineering
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    • v.21 no.9
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    • pp.12-19
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    • 2004
  • 수십 MN(10/sup 6/ N) 이상의 하중을 다루는 건설산업 및 중공업으로부터 수십 kN- 수 MN의 힘을 사용하는 재료시험기, 프레스, 및 공장 자동화설비 그리고 수십 N-수 kN 용량의 상업용 저울까지 힘 측정은 산업의 근간이 되는 기술이며 우리 실생활에 폭 넓게 이용되고 있다. 제품을 생산하고 대형 구조물을 건설하는 공장이나 건축현장에서 힘을 정확히 측정한다는 것은 공정을 일정하게 유지 관리하고 있다는 표시이므로 제품의 품질관리나 건축물의 안전관리의 척도가 된다. (중략)

AN IMMUNOHISTOLOGIC STUDY ON THE ACTIVITY OF MACROPHAGE AND T-CELL IN THE PERIODONTIUM DURING TOOTH MOVEMENT OF DOG (성견의 실험적 치아이동시 치주조직내 대식세포와 T-림파구의 활성에 관한 면역조직화학적 연구)

  • Park, Eui-Woong;Kim, Sang-Cheol;Kook, Yoon-A
    • The korean journal of orthodontics
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    • v.25 no.4
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    • pp.433-445
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    • 1995
  • Tooth movement, the phenomena and mechanisms of which are still controversial, can be considered as part of the result of the inflammatory processes. The purpose of this study was to examine the activity of macrophage and T-cell, playing important roles in the immune reaction, in the periodontal ligament of dog, in which experimental tooth movement was performed. Six one and half year-old dogs, a control and 5 experimentals, were studied. Light force (50-75g) was applied by placing open-coil spring between left mandibular premolars ; heavy force (250-300g), between right mandibular premolars. Experimental dogs were sacrificed at 12 hours, 1, 3, 7 and 14 days since force application, respectively. And the histologic and the immunohistochemical evaluation on the obtained tissue were performed, using $\alpha$-1-antichymotrypsin and CD3 antibodies. The results were as follows : 1. There were more inflammatory cell infiltrations in heavy force group than in light force group until 3 days. But from 7 dsays on, no difference was not observed between groups ; Such an infiltration was more evident at pressure side than at tension side. 2. Osteoclastic activity at pressure side began to be seen in 12 hours, increasing until 7 days. After then it decreased ; Such an activity was more evident in heavy force group than in light force group. 3. Tearing of periodontal ligament and vascular dilatation at tension side began to be seen in 12 hours, increasing until 3 days. After then it decreased ; Such an observation was more evident in heavy force group than in light force group, but there was no difference between groups in 14 days. 4. $\alpha$-1-antichymotrypsin expression in control group was positive, mainly in sulcular epithelium, but negative in periodontal membrane, pulp, bone cells. 5. $\alpha$-1-antichymotrypsin expression in experimental group was more positive in pressure side than in tension side ; The expression was a little more positive in cervical area of tooth until 3 days, but after 7days, it was more positive in apical area. 6. $\alpha$-1-antichymotrypsin expression in light force group began to be observed in 12 hours and reached to the greatest level in 7 days, after which it decreased ; In heavy force group, it was the greatest in 3 days, after which it decreased. 3 Expression in the periodontium was almost negative.

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