• Title/Summary/Keyword: anchorage system

Search Result 221, Processing Time 0.026 seconds

STUDY OF MAXILLARY CORTICAL BONE THICKNESS FOR SKELETAL ANCHORAGE SYSTEM IN KOREAN (Skeletal Anchorage System의 식립을 위한 한국인 악골의 피질골 두께에 대한 연구)

  • Kim, Ji-Hyuck;Joo, Jae-Yong;Park, Young-Wook;Cha, Bong-Kuen;Kim, Soung-Min
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • v.28 no.4
    • /
    • pp.249-255
    • /
    • 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.

Local dynamic characteristics of PZT impedance interface on tendon anchorage under prestress force variation

  • Huynh, Thanh-Canh;Lee, Kwang-Suk;Kim, Jeong-Tae
    • Smart Structures and Systems
    • /
    • v.15 no.2
    • /
    • pp.375-393
    • /
    • 2015
  • In this study, local dynamic characteristics of mountable PZT interfaces are numerically analyzed to verify their feasibility on impedance monitoring of the prestress-loss in tendon anchorage subsystems. Firstly, a prestressed tendon-anchorage system with mountable PZT interfaces is described. Two types of mountable interfaces which are different in geometric and boundary conditions are designed for impedance monitoring in the tendon-anchorage subsystems. Secondly, laboratory experiments are performed to evaluate the impedance monitoring via the two mountable PZT interfaces placed on the tendon-anchorage under the variation of prestress forces. Impedance features such as frequency-shifts and root-mean-square-deviations are quantified for the two PZT interfaces. Finally, local dynamic characteristics of the two PZT interfaces are numerically analyzed to verify their performances on impedance monitoring at the tendon-anchorage system. For the two PZT interfaces, the relationships between structural parameters and local vibration responses are examined by modal sensitivity analyses.

Suggestions for Improvement Things for Group Anchorage Safety Management (집단 정박지 안전관리 개선방안에 대한 제언)

  • Sang-Won Lee;Sun-Mi Jeong;Yun-Ha Kim
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
    • /
    • 2022.06a
    • /
    • pp.24-25
    • /
    • 2022
  • Based on the case of Busan Port November anchorage, which is a group anchorage, related regulations to promote group anchorage safety management, the turning radius of anchored ship, and more accurate weather information collection and safety through improvement of the supporting system for VTS operations to apply the anchorage location in accordance with reality that it is a suggestion for management improvement methods.

  • PDF

Behavior of steel-concrete composite cable anchorage system

  • Gou, Hongye;Wang, Wei;Shi, Xiaoyu;Pu, Qianhui;Kang, Rui
    • Steel and Composite Structures
    • /
    • v.26 no.1
    • /
    • pp.115-123
    • /
    • 2018
  • Steel-concrete composite structure is widely applied to bridge engineering due to their outstanding mechanical properties and economic benefit. This paper studied a new type of steel-concrete composite anchorage system for a self-anchored suspension bridge and focused on the mechanical behavior and force transferring mechanism. A model with a scale of 1/2.5 was prepared and tested in ten loading cases in the laboratory, and their detailed stress distributions were measured. Meanwhile, a three-dimensional finite element model was established to understand the stress distributions and validated against the experimental measurement data. From the results of this study, a complicated stress distribution of the steel anchorage box with low stress level was observed. In addition, no damage and cracking was observed at the concrete surrounding this steel box. It can be concluded that the composite effect between the concrete surrounding the steel anchorage box and this steel box can be successfully developed. Consequently, the steel-concrete composite anchorage system illustrated an excellent mechanical response and high reliability.

The use of miniscrew as an anchorage for the orthodontic tooth movement (Miniscrew를 고정원으로 이용한 교정치료)

  • Kyung, Seung-Hyun;Lim, Jung-Ki;Park, Young-Chel
    • The korean journal of orthodontics
    • /
    • v.31 no.4 s.87
    • /
    • pp.415-424
    • /
    • 2001
  • Anchorage in orthodontics is very important factor for orthodontist to treat malocclusion from diagnosis and treatment planning to end of treatment. Skeletal anchorage like miniscrew is supposed to be more effective method in anchorage control than conventional anchorage which needs patient's good cooperation. So this article will be mentioned about various clinical application of miniscrew through the general investigation and case reports about orthodontic use of miniscrew, specially about screwing area and clinical consideration of miniscrew's screwing on midpalate. The changes of treatment philosophy and methods by using skeletal anchorage were summarized and following results were obtained. 1. The orthodontic anchorage changed from relative concept to absolute one. 2. Bodily movement of teeth gets easier and determinate force system is possible on biomechanical consideration. 3. Some part of treatment that needs surgical intervention is possible by just orthodontic treatment.

  • PDF

Review of Anchorage Systems for Externally Bonded FRP Laminates

  • Grelle, Stephen V.;Sneed, Lesley H.
    • International Journal of Concrete Structures and Materials
    • /
    • v.7 no.1
    • /
    • pp.17-33
    • /
    • 2013
  • The most recent report by ACI Committee 440 on externally bonded fiber reinforced polymer (FRP) strengthening systems states that systems designed to mechanically anchor FRP should be studied in detail and substantiated by physical testing. To select and design an appropriate anchorage system for use in an FRP strengthening system, it is important that findings from previous research studies be known. This paper presents a comprehensive literature review of the performance of different mechanical anchorage systems used in FRP strengthening applications. Each anchorage system is discussed in terms of its purpose and performance. Advantages and disadvantages of each system are discussed, and areas in need of future research are explored.

Experimental Study on the Performance of Korean PS Anchorage System in terms of Load Transfer Test (한국형 PS정착구의 하중전달성능에 관한 연구)

  • Kim, Jin-Kook;Lee, Pil-Goo;Jang, Seok-Youn
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2009.05a
    • /
    • pp.37-38
    • /
    • 2009
  • In this paper, the load transfer test of Korean PS anchorage system was conducted for 1860MPa PS strand and 2200MPa PS strand. The test is in compliance with ETAG013. All the anchorage system tested satisfied the allowance criteria of the test for 1860MPa PS strand but only one of the anchorage systems for 2200MPa PS strand. In order to generally use 2200MPa PS strand to prestressed concrete structures, new anchorage systems shall be developed.

  • PDF

An Experimental Study on the Performance of Compression-Type Anchor for CFRP Tendons (CFRP 긴장재용 압착형 정착장치의 정착성능에 관한 실험적 연구)

  • Jung, Woo-Tai;Lee, Seung-Joo;Park, Young-Hwan
    • Journal of the Korea Concrete Institute
    • /
    • v.20 no.5
    • /
    • pp.611-618
    • /
    • 2008
  • CFRP (carbon fiber reinforced polymer) tendons can be used as an alternative to solve the corrosion problem of steel tendons. Since CFRP tendons are vulnerable to transverse pressure and stress concentration, the conventional anchorage system used for steel tendons can create an unreliable load carrying capacity and may result in a premature failure. Therefore, it is necessary to develop the anchorage system that is well suited for CFRP tendons. There are many types of anchorage systems for CFRP tendons, which can be classified into three types: wedge-type anchorage, bond-type anchorage, and compression-type anchorage. This paper deals with the compression-type anchorage system manufactured through swaging technology. Based on the previous test results performed by the authors, the dimension of anchorage sleeve, the use and non-use of the insert, and the compression pressure on the sleeve have been selected as the major parameters affecting the performance of the compression-type anchorage. Some anchorage sleeves have been tapered to reduce the stress concentration. Test results revealed that the performance of the anchorage system depends mainly on the dimension and the compression pressure. It has been verified that the tapered sleeve can effectively reduce the stress concentration.

THE USE OF MINISCREWS FOR TOOTH MOVEMENT IN CHILDREN (성장기 아동에서 miniscrew를 고정원으로 이용한 치아이동)

  • Kim, Sang-Min;Park, Ho-Won;Lee, Ju-Hyun;Seo, Hyun-Woo
    • Journal of the korean academy of Pediatric Dentistry
    • /
    • v.37 no.4
    • /
    • pp.537-544
    • /
    • 2010
  • Anchorage control in orthodontic treatment is an important factor affecting treatment results. In the conventional approach, intra-oral anchorage such as application of differential force and moment, Nance holding arch and lingual arch, as well as extra-oral anchorage such as head gear were used for anchorage reinforcement. However, these anchorages may result in undesired tooth movement and require patient cooperation. To overcome these disadvantages, skeletal anchorage system was introduced as orthodontic anchorage. Types of skeletal anchorage include implant, onplant, miniplate and miniscrew. Especially, miniscrew has many advantages such as reduced patient cooperation, low cost and easy placement. Recently, it is successfully used in orthodontic treatment. This cases were treated using orthodontic miniscrews for retraction of ectopically erupting maxillary canine and impacted mandibular canine and intrusion of maxillary incisors.