• 대한심미치과학회지
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• 제26권1호
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• pp.24-38
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• 2017

치과 임상에서 보철 과정은 1) 치아 삭제 2) 임시 수복물 제작 3) 포스트와 코어 4) 인상채득 5) 최종 보철물 합착의 순서로 진행된다. 보철 과정의 마지막이 정확한 적합과 교합 관계를 갖는 최종 보철물을 환자의 지대치의 적합시키는 과정이다. 그런데, 이 최종 보철물은 진료실에서 만들어지는 것이 아니라, 치과 기공실에서 만들어져서 약간의 시간차를 두고 진료실로 오게 된다. 진료실에서 환자의 구강 내 정보를 기공실로 전달하는 유일한 매체는 인상체이다. 그런데 이 과정에서 수 많은 오차가 발생된다. 치과 의사와 치과 기공사는 이 오차를 줄이기 위해 원인을 파악하고 정확한 보철물 제작을 위해 노력해야 한다.

• The Korean Journal of Physiology and Pharmacology
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• 제13권3호
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• pp.221-227
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• 2009

For successful restoration of visual function by a visual neural prosthesis such as retinal implant, electrical stimulation should evoke neural responses so that the informat.ion on visual input is properly represented. A stimulation strategy, which means a method for generating stimulation waveforms based on visual input, should be developed for this purpose. We proposed to use the decoding of visual input from retinal ganglion cell (RGC) responses for the evaluation of stimulus encoding strategy. This is based on the assumption that reliable encoding of visual information in RGC responses is required to enable successful visual perception. The main purpose of this study was to determine the influence of inter-dependence among stimulated RGCs activities on decoding accuracy. Light intensity variations were decoded from multiunit RGC spike trains using an optimal linear filter. More accurate decoding was possible when different types of RGCs were used together as input. Decoding accuracy was enhanced with independently firing RGCs compared to synchronously firing RGCs. This implies that stimulation of independently-firing RGCs and RGCs of different types may be beneficial for visual function restoration by retinal prosthesis.

• 구강회복응용과학지
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• 제22권4호
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• pp.341-348
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• 2006

Accurate fit of the implant prosthesis is important in ensuring long term success of osseointegrated implant. Inaccurate fit of the implant prosthesis may give rise to complications and mechanical failure. To evaluate fite of the implant prosthesis, the development of the methods of analyzing the degree of misfit is important in clinical practice. To analyze the degree of the misfit of implant prosthesis, modal testing was used. A 2-dimensional finite element modal testing was accomplished. Four 2-dimensional finite element models with various levels of misfit of implant prostheses were constructed. Thickness gauges were simulated to make misfit in the implant prostheses. With eigenvalue analysis, the natural frequencies of the models were found in the frequency domain representation of vibration. According to the difference of degree of misfit, natural frequencies of the models were changed.

• 구강회복응용과학지
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• 제22권3호
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• pp.251-260
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• 2006

Accurate fit of the implant prosthesis is important in ensuring long term success of osseointegrated implant. Inaccurate fit of the implant prosthesis may give rise to complications and mechanical failure. To evaluate fite of the implant prosthesis, the development of the methods of analyzing the degree of misfit is important in clinical practice. To analyze the degree of the misfit of implant prosthesis, modal testing was used. A 2-dimensional finite element modal testing was accomplished. Four 2-dimensional finite element models with various levels of misfit of implant prostheses were constructed. Thickness gauges were simulated to make misfit in the implant prostheses. With eigenvalue analysis, the natural frequencies of the models were found in the frequency domain representation of vibration. According to the difference of degree of misfit, natural frequencies of the models were changed.

• 대한치과의사협회지
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• 제50권3호
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• pp.126-139
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• 2012

Loss of dentition can lead to not only compromised esthetics and functions of the patient, but also alveolar bone resorption. Bone grafting with prosthetic reconstruction of the gingiva can be selected for the treatment, and it provides many benefits as prosthetic gingival reconstruction does not require a complicated surgical process and is available within a short period of time, with stable clinical results. However, conventional porcelain fused to metal prosthesis has certain limits due to its size, and deformation after several firing procedures. In this clinical report, the author would like to introduce a patient with severe alveolar resorption who was treated with gingiva-shaped zirconia/titanium CAD/CAM implant fixed prosthesis for esthetic and functional rehabilitation. Clinical reports Clinical report 1, 2 : A case of loss of anterior dentition with atrophied alveolar bone. Implant retained zirconia bridge applied with Procera implant bridge system to simulate the gingiva. Upper structure was fabricated with zirconia all ceramic crown. Clinical report 3, 4 : A case of atrophied maxillary alveolus was reconstructed with fixed implant prosthesis, a CAD/CAM designed titanium structure covered wi th resin on its surface. Anterior dentition was reconstructed with zirconia crown. Conclusion and clinical uses. All patients were satisfied with the outcome, and maintained good oral hygiene. Zirconia/titanium implant fixed prosthesis fabricated by CAD/CAM system was highly accurate and showed adequate histological response. No critical failure was seen on the implant fixture and abutment overall. Sites of severe alveolar bone loss can be rehabilitated by implant fixed prosthesis with CAD/CAM system. This type of prosthesis can offer artificial gingival structure and can give more satisfying esthetics and functions, and as a result the patients were able to accept the outcome more fondly, which makes us less than hard to think that it can be a more convenient treatment for the practitioners.

• Journal of Chest Surgery
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• 제24권3호
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• pp.265-270
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• 1991

Since advent of the prosthetic cardiac valve replacement, much efforts for accurate assessing value function in-vivo have been attempted. To evaluate the postoperative functional and morphological status of the replaced cardiac valve prosthesis, 33 patients with valve replacement were studied by transthoracic and transesophageal 2-dimensional echocardiac imaging as well as by color Doppler flow velocity imaging. Twenty four patients had mitral valve replacement. 6 patients had aortic valve replacement and 3 patients had both mitral and aortic valve replacement. There were 34 mechanical and 2 biological prosthesis. Comparing to transthoracic echocardiography, transesophageal approach showed transvalvular regurgitant jet flow amid the prosthetic mitral valve ring during. systole and much clear visualization of cardiac chamber behind prosthesis which could give shadowing effect to ultrasound beam. According to the quantitative grading by the length and area of mitral regurgitant flow, 24 out of 27 mitral valves revealed mild degree regurgitation considered as physiological after prosthetic bileaflet valve replacement and the other 3 valves including 2 biological prosthesis had moderate degree regurgitation which was regarded as pathologic one. 2 cases of left atrial thromboses and 1 case of paravalvular leakage which were not visible by transthoracic approach were identified by transesophageal echocardiography in patients with mitral valve replacement and patients with aortic valve replacement respectively. We conclude that in patients with prosthetic mitral valve replacement, transesophageal 2-dimensional imaging with color Doppler can suggest reliable information beyond that available from the transthoracic access even though it gives patient some discomfort to proceed.

• 대한치과보철학회지
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• 제53권3호
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• pp.256-261
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• 2015

임플란트 보철물의 경우 무엇보다도 보철물의 정확성이 중요하며 이러한 이유로 인해 인상채득의 정확성을 확인하는 과정이 필수적이다. 그러나 인상재 자체의 오차가 존재하며 모형을 제작하는 과정에서도 오차가 발생하게 된다. 이에 대한 대안으로 구강스캐너를 통한 보철물 제작을 생각해 볼 수 있으며, 최근 구강스캐너와 기존의 인상법 간의 정확성에 있어 통계적으로 유의할만할 차이가 없다는 많은 문헌들이 발표되었다. 따라서 intraoral scanner를 이용하여 기존에 방법에 비해 보다 편하고, 빠르며, 정확한 임플란트 보철물을 제작하는 일련의 과정을 보고하고자 한다.

• 대한심미치과학회지
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• 제26권1호
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• pp.52-63
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• 2017

상하악 풀마우스 보철을 만들어주어야 할때 정확한 진단을 하고 계획을 잘 세워서 보철물을 디자인해야 한다. 특히 교합고경이 무너지고 잘못된 교합평면으로 인한 환자의 경우에는 예전의 교합고경으로 회복시켜주어야 하고 올바른 교합평면을 만들어 주어야 한다. 또한 적절한 재료를 사용하여 환자가 음식을 잘 저작하고 무리한 힘이 가해지지 않도록 해야한다. 임플란트의 위치가 부적절한 위치에 있을때는 보철물을 디자인할때 대합치와의 관계와 교합등을 고려하여 결정한다. 그리고 임플란트 주변의 청소성을 위한 디자인을 해주어야 한다.

• 대한치과보철학회지
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• 제60권4호
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• pp.382-394
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• 2022

심한 치주염을 가진 환자의 치료는 환자의 개개 치아의 정확한 진단과 전략적인 치료 계획을 통해 단계적으로 진행되어야 한다. 임플란트 지지 고정성 보철 수복은 국소의치에 비해 환자의 만족도가 높고, 안정적인 수직 고경을 유지할 수 있는 장점이 있지만, 경조직이 부족한 다수 치아 결손 부위에서는 심미적인 측면의 실패와 치료 기간이 길어진다는 점의 단점이 있을 수 있다. 또한 통상의 고정성 보철물을 제작하고 장착하는 데에는 일정 기간이 소요되는데, 이 기간 동안 임시 보철물은 치아의 기계적, 생물학적, 심미적 요구 조건을 만족시켜야 한다. 이번 증례 보고에서는 상악과 하악의 부분 무치악 환자에서 단계적인 접근을 통한 임플란트 고정성 보철물을 수복한 증례를 보고하고자 한다.

• 구강회복응용과학지
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• 제33권2호
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• pp.63-70
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• 2017

임상적으로 고정성보철물의 적합도는 성공적인 수복을 위해 필수적인 요소이다. 보철물의 적합도는 크게 변연적합도와 내면적합도로 분류되며, 이를 평가하기 위한 방법으로는 현미경 변연 측정법, 절단면 측정법, 실리콘 복제법, 3차원 스캔데이터 중첩법, 무게 측정법, 마이크로 CT 측정법 등 다양한 방법들이 소개되고 있다. 이에 본 연구에서는 기존의 문헌들을 바탕으로 각 방법들의 장, 단점을 비교분석함으로써 디지털환경에서 보다 편리하고 정확한 측정법을 제시하고자 한다.