• Title/Summary/Keyword: 심한 마모

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Development of the coating materials consisting of Zr-Al-Cu for nano structured coating and investigation of their friction behavior (Zr-Al-Cu계 나노구조 코팅재 설계개발 및 윤활마찰거동 조사)

  • Sin, Seung-Yong;Mun, Gyeong-Il;Seon, Ju-Hyeon
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2014.11a
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    • pp.17-18
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    • 2014
  • 최근 자동차 성능 및 연비향상을 위해서 엔진의 고출력화 및 소형화 경향이 뚜렷해지고 있으며, 이로 인해 엔진내부의 부품이 받는 환경은 더욱 가혹해 지고 있다. 즉, 자동차 엔진 구동부품은 금속간의 접촉가능성이 매우 높은 경계윤활조건에 놓이게 되며, 또한 배기가스 규제로 인한 첨가제를 최소화 하려는 경향에 따라 경계윤활 환경에서 더욱 심한 마모문제에 직면할 것으로 예상되어 내구성 및 내마모성이 높은 코팅기술에 대한 요구가 더욱 증가하고 있다. 본 연구에서는 Zr기지의 비정질 형성능을 갖는 합금계를 이용하여 아르곤 및 질소분위기에서 스퍼터링 함으로써 고경도의 ZrN상과 엔진오일과 반응하여 저마찰 트라이보 필름을 형성시킬 수 있는 금소계 원소가 Tissue phase로 존재하는 질화물 나노박막합성기술을 개발한 후 자동차 구동부품인 벨브트레인계 및 피스톤링/라이너 부품에 적용하여 마찰특성을 평가하였다.

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Full-mouth rehabilitation of a patient with severe tooth wear using fixed prosthesis (마모가 심한 환자의 전악 고정성보철물 제작 증례)

  • Kim, Wook Tae
    • Journal of Technologic Dentistry
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    • v.42 no.4
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    • pp.409-417
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    • 2020
  • This case study is aimed at introducing a full-mouth rehabilitation of a patient with severe tooth wear using fixed prosthesis. This is a case report of a patient with severe wear dentition with changing vertical dimension. In line with using prosthetic treatment, patient adaptation was verified with provisional restorations followed by diagnostic wax-up. Function, esthetics, and occlusal stability were verified during a 4-week follow up period. Prosthodontic reconstruction based on systemic analysis, diagnosis, and treatment plan led to satisfactory results after delivery of definitive prosthesis. Prosthetic treatment of severe wear dentition was functionally and esthetically successful. Dentists and dental technicians would be able to develop better treatment approaches using fixed dental prosthesis.

Experimental brush wear pattern and cariostatic effect of Biscover (Biscover의 잇솔질에 따른 마모양상과 항우식 효과)

  • Oh, Eun-Ju;Park, Song-Soo;Jang, Mun-Ju;Jeon, Young-Mi;Kim, Jong-Ghee
    • The korean journal of orthodontics
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    • v.38 no.3
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    • pp.214-222
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    • 2008
  • Objective: The aim of this study was to investigate the experimental brush wear pattern of a light cured surface sealant, Biscover (Bisco, Schaumburg, IL), and to evaluate its cariostatic effect. Methods: Caries-free human premolars were used for the Biscover coating group (n = 90) and the control group (n = 10). The Biscover coating group was randomly assigned to nine subgroups of 10 each and the control group was assigned to two subgroups of 5 each according to the number of brushing strokes. An experimental 3-body wear test was conducted under different strokes of wear test. Tooth-brushing was accomplished with movement of each brush head set at a frequency of 100 rpm under a force of 1.5N, Surface roughness was tested before, and after Biscover coating, and after brushing. Then, each of the 10 teeth of both groups were placed in artificial caries inducing solution for 7 days. All tooth surfaces were assessed using scanning electron microscopy. Results: Biscover coated surfaces showed a smoother texture than enamel surfaces. The roughness was increased after experimental brushing and after 10,800 brushing strokes, the whole layer of Biscover wore out. However, teeth in the Biscover coating group had a cariostatic effect in cariogenic conditions. Conclusions: We suggest that white lesions in orthodontic patients can be suppressed by topical applications of Biscover.

Oral rehabilitation of a young adult with amelogenesis imperfect using metal-ceramic restoration: a clinical report (금속 도재 수복물을 이용한 청년기 법랑질 이형성증 환자의 수복증례)

  • Kim, Hong-Jun;Lee, Jae-Hoon;Han, Dong-Hoo;Moon, Hong-Suk
    • The Journal of Korean Academy of Prosthodontics
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    • v.50 no.3
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    • pp.210-215
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    • 2012
  • Some patients with generalized attrition and teeth discoloration may want their anterior teeth to be treated just for esthetic improvement. Ameologenesis imperfecta, however, should be considered for such patients prior to any treatment with thorough clinical and radiographic examination. If a patient is diagnosed with amelogenesis imperfecta, the treatment on anterior teeth just for esthetic purpose is not advisable. In this case, a young man with amelogenesis imperfecta was treated with metal-ceramic restorations. The patient had generalized attrition, teeth discoloration, crown fracture, and cross-bite on the left teeth. The ultimate objective of this treatment was to enhance esthetics and masticatory function. The cross-bite on the left anterior teeth was treated with restorations, whereas the reverse horizontal overlap was maintained on the posterior. The patient was satisfied with the result esthetically and functionally, and the third month recall examination revealed no pathologic changes associated with the treatment.

Case report: Laminate prosthesis with orthodontic treatment for achieve anterior esthetics and functional occlusion (심미와 기능 회복을 위한 교정- 라미네이트 수복 치료 증례)

  • Lee, Han Na
    • Journal of the Korean Academy of Esthetic Dentistry
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    • v.23 no.2
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    • pp.80-85
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    • 2014
  • Orthodontic treatment is obviously the first choice to get aligned teeth cause of conservative treatment. But it is impossible to get highly esthetic result only orthodontic treatment in case of peg lateralis, discrepancy tooth size, discolored teeth or fractured teeth. As all treatment does, especially in esthetic treatment it is always required interdisciplinary diagnosis and treatment plan; orthodontics, periodontology, prothetics, implant therapy. As also, the treatment should be maintained long-term treatment with stable and harmonious state by esthetic satisfaction and functional occlusion those who needs various dental care as interdisciplinary treatment. This case is the laminate treatment with the orthodontic treatment on 37 ages/ Female patient who has cross bite at anteriors and premolar area and abrasion on centralis at right maxilla. By orthodontic treatment aligned teeth positions, it makes functional occlusion. As laminate treatment with minimum teeth preparation is able to release anterior esthetics. Follow up check for 2 years has been performed since the final prosthetics delivery to the patient. No sign of relapse, fracture of laminate were detected.

A Design of the Automation Tyre Tread State Check System based on IoT Service (IoT 서비스 기반 자동차 타이어 트레드 자동 점검 시스템 설계)

  • Kim, Minyoung;Choi, Donggyu;Jang, Jong-wook
    • The Journal of the Convergence on Culture Technology
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    • v.6 no.4
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    • pp.825-831
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    • 2020
  • In modern society, automobiles have become an essential means of transportation. It is the only consumable that is worn by contacting the ground among automobile parts. If the tyres are severely worn, the tyres may be break, presenting a risk of a serious accident to the driver. To avoid this risk, drivers should check tyre pressure and tread condition before driving a car. Tyre inflation pressure can be easily measured by TPMS, but in the case of tyre tread conditions, it can be cumbersome when the driver measures it directly using a coin or vernier caliper. This hassle can expose the driver to traffic accidents due to tyre breakage by neglecting to measure the condition of the tyre tread. In this paper, we introduce the contents of research to design an IoT service-based system that can automatically measure automobile tyres, and we verified the possibility of realizing the system by actually implementing and testing some components of the system.

Full mounth rehabilitation using OP finder® system for patient with inadequate occlusal plane and multiple occlusal wear tooth state: a case report (부적절한 교합평면과 다수의 교합면 마모를 가진 환자에서 OP finder® system을 이용한 전악 수복증례)

  • Lee, Seon-Ki
    • Journal of Dental Rehabilitation and Applied Science
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    • v.37 no.3
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    • pp.138-146
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    • 2021
  • The diagnosis and treatment plan for forming ideal occlusal plane in full mouth rehabilitation are difficult because each process is complicated and information exchange between dentist and technician is subjective. The OP finder® system simplifies this process and helps to deliver more objective and accurate information. In this case, full mouth rehabilitation was performed using OP finder® system for patients with old bad fixed prosthesis and severely worn mandibular teeth, and reported that the result of proper occlusal plane setting and masticatory function recovery was obtained.

Evaluation of Color Coating Method for Color Maintenance of Color Asphalt Pavement (칼라 아스팔트 포장의 색채 표면보수를 위한 칼라코팅 공법 성능평가)

  • Park, Tae-Soon
    • International Journal of Highway Engineering
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    • v.13 no.4
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    • pp.93-101
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    • 2011
  • The evaluation of various color coating methods for color maintenance of color asphalt pavement is conducted using the laboratory and field tests on the bus lane. The surface of color asphalt constructed on the bus lane is deteriorated such as changing color and decoloration and abrasion due to the passing of the traffic and time. The total of 9 coating methods were evaluated in this study. The laboratory tests included Ultra violet test, adhesion test and Taber abrasion test and the field tests were british pendulum test and visual survey. The results of tests showed that the different methods showed the their own engineering characteristics and it is dependant upon the main material used. The rubber epoxy material for the main material showed the satisfactory result among the methods tested. However, the performance of the coating methods after 100days are not satisfactory, decoloration, abrasion and peeling up are investigated and need to be studied for the further application in the field.

Influence of airborne-particle abrasion on flexural strength of fiber-reinforced composite post (미세입자 분사마모 표면처리가 Fiber-Reinforced Composite 포스트의 굴곡 강도에 미치는 영향)

  • Sim, Eun-Ju;Kim, Jin-Woo;Cho, Kyung-Mo;Park, Se-Hee
    • Journal of Dental Rehabilitation and Applied Science
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    • v.32 no.1
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    • pp.24-31
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    • 2016
  • Purpose: Many studies have shown that airborne-particle abrasion of fiber post can improve the bonding strength to resin cement. But, airborne-particle abrasion may influence the property of fiber post. The purpose of this study is to evaluate the influence of airborne-particle abrasion on flexural strength of fiber post. Materials and Methods: Two fiber-reinforced posts; DT Light Post Size 2 (1.8 mm diameter, Bisco Inc) and RelyX Fiber Post Size 3 (1.9 mm diameter, 3M ESPE); were used in this study. Each group was divided into 3 subgroups according to different surface treatments; without pretreatment: $50{\mu}m$ aluminum oxide (Cobra$^{(R)}$, Renfert): and $30{\mu}m$ aluminum oxide modified with silica (Rocatec Soft$^{(R)}$, 3M ESPE). After airborne-particle abrasion procedure, three-point bending test was done to determine the flexural strength and flexural modulus. The diameter of each posts was measured to an accuracy of 0.01 mm using a digital micrometer. There was no diameter change before and after airborneparticle abrasion. The mean flexural moduli and flexural strengths calculated using the appropriate equations. The results were statistically analyzed using One-way ANOVA and Scheffe's post-hoc test at 95% confidencial level. Results: There was no significant difference on flexural strength between groups. Conclusion: In the limitation of this study, flexural strength and flexural modulus of fiber post are not affected by airborne-particle abrasion.

A CASE REPORT OF DENTINOGENESIS IMPERFECTA (상아질 형성부전증에 대한 증례 보고)

  • Jun, Eun-Min;Kim, Eun-Jung;Kim, Hyun-Jung;Kim, Young-Jin;Nam, Soon-Hyeun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.33 no.2
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    • pp.323-328
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    • 2006
  • Dentinogenesis imperfecta is an inheritable disease of dentinal defect, generally is inherited as a single autosomal dominant trait. It has a prevalence of 1 in 8000 with the trait, and no significant difference between male and female, with involvement of the primary and permanent teeth. Shields proposed three types of Dentinogenesis imperfecta. Affected teeth have various discoloration, separation of enamel rapid destruction of underlying dentin, and severe attrition. Radiographically, the teeth have cervical constriction, bulbous crown, thin root, obliteration of the root canals and pulp chambers, and periapical lesions in a sound tooth. The objective of treatment is rehabilitation of the esthetics, the masticatory function, and the vertical dimension of occlusion. In these cases, two pediatric patients reported to the Kyungpook University Pediatric clinic, with a chief complaint of discolored teeth and severe attrition. As a result of clinical and radiographic exam, it was diagnosed as Dentinogenesis imperfecta. The posterior teeth were restored with Stainless Steel Crown, and the anterior teeth were restored with composite resin veneering.

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