• Hip & pelvis
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• 제36권2호
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• pp.101-107
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• 2024

Treatment of femoral bone defects continues to be a challenge in revision total hip arthroplasty (THA); therefore, meticulous preoperative evaluation of patients and surgical planning are required. This review provides a concise synopsis of the etiology, classification, treatment strategy, and prosthesis selection in relation to femoral bone loss in revision THA. A search of literature was conducted for identification of research articles related to classification of bone loss, management of femoral revision, and comparison of different types of stems. Findings of a thorough review of the included articles were as follows: (1) the Paprosky classification system is used most often when defining femoral bone loss, (2) a primary-length fully coated monoblock femoral component is recommended for treatment of types I or II bone defects, (3) use of an extensively porous-coated stem and a modular fluted tapered stem is recommended for management of types III or IV bone defects, and (4) use of an impaction grafting technique is another option for improvement of bone stock, and allograft prosthesis composite and proximal femoral replacement can be applied by experienced surgeons, in selected cases, as a final salvage solution. Stems with a tapered design are gradually replacing components with a cylindrical design as the first choice for femoral revision; however, further confirmation regarding the advantages and disadvantages of modular and nonmodular stems will be required through conduct of higher-level comparative studies.

• 전력전자학회논문지
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• 제11권2호
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• pp.97-103
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• 2006

본 논문은 회전형 대용량 진단 X-선 발생장치를 모노 블록 형태로 설계, 병원의 모바일 진단장치나, 산업용 X-선 장치로에 적용이 가능한 16kW급 회전 Anode형 모노블럭 X-선 발생장치에 관한 연구이다. 본 장치는 X-선 발생을 위해 회전 Anode 형의 X-선관을 사용하였고, X-선관의 Anode의 회전을 위한 로터를 구동할 수 있는 로터 구동회로를 추가 하였다. 고주파 고전압용 인버터에는 IGBT(600V/300A)소자를 100kHz로 고주파 스위칭 함으로서 고전압 변압기를 비롯한 고전압 발생부의 크기와 무게를 최소화하였다. 또한, 기존의 16kW급 대용량 진단 X-선 발생장치를 X-선관과 고전압부를 일체화한 모노블록 형태로 설계, 제작하여 부하변동에 따른 X-선 관전압과 관전류의 동작특성을 실험을 통하여 입증하였다.

• Restorative Dentistry and Endodontics
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• 제41권2호
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• pp.114-120
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• 2016

Objectives: The aim of this study was to compare the push-out bond strength and dentinal tubule penetration of root canal sealers used with coated core materials and conventional gutta-percha. Materials and Methods: A total of 72 single-rooted human mandibular incisors were instrumented with NiTi rotary files with irrigation of 2.5% NaOCl. The smear layer was removed with 17% ethylenediaminetetraacetic acid (EDTA). Specimens were assigned into four groups according to the obturation system: Group 1, EndoRez (Ultradent Product Inc.); Group 2, Activ GP (Brasseler); Group 3, SmartSeal (DFRP Ltd. Villa Farm); Group 4, AH 26 (Dentsply de Trey)/gutta-percha (GP). For push-out bond strength measurement, two horizontal slices were obtained from each specimen (n = 20). To compare dentinal tubule penetration, remaining 32 roots assigned to 4 groups as above were obturated with 0.1% Rhodamine B labeled sealers. One horizontal slice was obtained from the middle third of each specimen (n = 8) and scanned under confocal laser scanning electron microscope. Tubule penetration area, depth, and percentage were measured. Kruskall-Wallis test was used for statistical analysis. Results: EndoRez showed significantly lower push-out bond strength than the others (p < 0.05). No significant difference was found amongst the groups in terms of percentage of sealer penetration. SmartSeal showed the least penetration than the others (p < 0.05). Conclusions: The bond strength and sealer penetration of resin-and glass ionomer-based sealers used with coated core was not superior to resin-based sealer used with conventional GP. Dentinal tubule penetration has limited effect on bond strength. The use of conventional GP with sealer seems to be sufficient in terms of push-out bond strength.