• The Journal of Advanced Prosthodontics
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• v.12 no.1
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• pp.15-21
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• 2020

PURPOSE. The aim of the current study was to analyze treatment concepts of a cohort of German dentists for planning, fabrication, and maintenance of implant-supported fixed and removable restorations. MATERIALS AND METHODS. A questionnaire including queries about experiences with implant-supported restorations as well as prosthetic and maintenance treatment concepts for supplying patients with fixed and removable implant-supported prosthetic restorations was developed and sent to 350 dental offices registered in the municipal area of Leipzig, Germany. RESULTS. An overall total of 62 returned questionnaires were included in the analyses, which relates to a response rate of 17.7%. Participating dentists were more involved in the prosthetic aspects of implant dentistry rather than surgery, while prosthetic concepts such as backward planning, digital processing, and application of all-ceramic materials were not commonly performed. Simple attachments were preferred over complex retention systems in removable implant-supported restorations. Tooth/implant-supported fixed denture prostheses as well as removable denture prostheses with supporting posterior implants were not regarded as a favorable treatment option. CONCLUSION. Within the limitations of the study, the data indicate that dentists favor simple and conventional treatment approaches in implant prosthetics. Prosthetic aspects in the planning of implant-supported restorations are often neglected. Prosthetic treatment guidelines and aspects should commonly be considered in the planning phase of implant-supported prosthetic restorations, and awareness should be increased in postgraduate education.

• Korean Journal of Applied Biomechanics
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• v.15 no.4
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• pp.131-142
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• 2005

This study was investigated the stability of the AK amputee gait through analysing the variability on kinematic variables between the sound leg and the prosthetic limb. The one male, AK amputee who could walk for himself with his prosthetic limb was participated in this study. Six cameras of the MCU 240 and the QTM(Qualisys Track Manager) software were used for data collecting in this study. The relative angle of both segments was the difference between the absolute angle of the distal segment and the absolute angle of the proximal segment. The coupling angles between the prosthetic limb and the sound leg were caculated on the thigh Flexion/Extension in relative to the shank Flexion/Extension and the shank Flexion/Extension n relative to the foot Flexion/Extension. In order to evaluate the variability of segment and joint angle, C.V. was used, and to evaluate the variability for coupling angles, the Relative motion calculated by vector coding method of the continuous methods was used. As stated, the gait pattern of the prosthetic limb was almost similar gait pattern of the sound leg, but the prosthetic limb showed that the gait pattern of the sound leg and the prosthetic limb were not stable against the sound leg.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2000.04a
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• pp.328-329
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• 2000

A viscosity resistance control method of the intelligent prosthetic legs is studied using an optimal control theory. The simulated results suggests that it is important to control the viscosity of the prosthetic knee joint in one period of walking to improve the usability. In this paper we describe modeling of the thigh prosthetic legs, optimal control and simulated results.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.1 no.2
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• pp.75-79
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• 2015

[$^{18}F$]Fluorobenzaldehyde, which is a versatile radioactive prosthetic group, can undergo reduction, reductive amination, or oxidation to be used for synthesis of diverse radiotracers. This review covers synthesis of [$^{18}F$]fluorobenzaldehyde and its conversion to secondary prosthetic groups, and also highlights its application to the development of radiotracers.

• Journal of Chest Surgery
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• v.9 no.2
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• pp.207-214
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• 1976

Operations for cardiac valvular disease has been progressed in various ways. Since 1949 when Lord Russel operated mitral stenosis by closed technique at Johns Hopkins Hospital then much progress has been achieved and that nowadays severely diseased cardiac valve has been replaced by prosthetic valve, which is almost ideal in hemodynamic aspect, but still it has many problems such as thromboembolism, destruction of red blood cell, pressure gradient, and disturbance of left ventricular function, so in case of delicate situations, valve replacement should be decided carefully. Besides prosthetic valve, there are some kinds of reconstructive procedures and these have been resulted in better prognosis than prosthetic valve replacement in selected cases. So, authors have reviewed 61 Cases of cardiac patients who have been operated reconstructive valvular surgery by cardiopulmonary bypass, at Yonsei University, from Jan. 1963 to Mar. 1976. Out of 61 cases, 9 patients were replaced by prosthetic valve and rest of the patients were operated upon in various reconstructive procedures such as commissurotomy, valvotomy, valvuloplasty, and annuloplasty. Twenty cases of congenital heart diseases with valvular lesion, which had been operated for valvular lesion were also included in this statistics. Out of 9 cases of prosthetic valvular replacement five cases of prosthetic valvular replacement was done combined with other reconstructive procedures after attempted valvuloplasty. Comparative prognosis of both procedures are somewhat variable by reporters, average 19% of mortality after reconstructive surgery and 38% of mortality after prosthetic valve replacement in long term results. Most common cause of death in postoperative period was low output syndrome in both cases. It seems that good preoperative evaluation and proper reconstructive surgery will afford good prognosis in selected cardiac valvular diseased patient.

• Journal of Technologic Dentistry
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• v.25 no.1
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• pp.119-142
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• 2003

In the present work the knowledge of dental health as well as dental prosthesis has been studied on the basis of analysis of current dental prosthetic treatments for dental diseases prophylaxis and the final decision for dental prosthetic appliance. The results have been analyzed by the current dental health care and the subjective acknowledgement from 700 people of urban as well as rural inhabitance in our country. The results from the present work have been summarized as following: Depending dental status has been shown worse to be in the cases of divorce and bereavement, age and less educated or jobless. It is also interesting to note that the dental status has shown to be even worse than health status. It has been shown that the dental prosthetic treatments have been mainly caused by the oral disease (62.2%) and depend on the age and the educational level. According to the actual status of dental prosthetic treatments, the fixed partial denture was the most case (78.9%) that increased as divorced, bereavement and as less educated, less income, retired and jobless as well as from urban to rural. As a clinic for the dental prosthetic treatments, dental clinics have been most frequent visited as indicated by 59.6%, then the un-licensed dentist (6.5%), then the hospitals (3.7%), then the public health centers (2.2%). Most of those who are older in age, less educated and jobless have been treated by the un-licensed dentists. In point of view on the cost for dental prosthetic treatments, 93.1% have claimed to be too expensive, in as the divorced and the bereaved, the older age, the less educated and the jobless. About satisfaction of dental prosthetic treatments, 51.4% was satisfied, 39.4% was normal and 9.2% was dissatisfied. Most of people experienced increasing levels of satisfaction as their income increase. Most in the age range of 40-60 have wanted to be insured for the dental prosthetic treatments. It is also interesting to note that the older age and the less educated wanted to apply this kind of insurance.

• Journal of Chest Surgery
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• v.28 no.1
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• pp.23-30
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• 1995

From January 1985 to December 1992, of 1257 patients who underwent a heart valve replacement 210 [16.8% underwent reoperation on prosthetic heart valves, and 6 of them had a second valve reoperation. The indications for reoperation were structural deterioration [176 cases, 81.5% , prosthetic valve endocarditis [25 cases, 11.6% , paravalvular leak [12 cases, 5.6% , valve thrombosis [2 cases, 0.9% and ascending aortic aneurysm [1 case, 0.4% . Prosthetic valve failure developed most frequently in mitral position [57.9% and prosthetic valve endocarditis and paravalvular leak developed significantly in the aortic valve [40%, 75% [P<0.02 . Mean intervals between the primary valve operation and reoperation were 105.3$\pm$28.4 months in the case of prosthetic valve failure, 61.5$\pm$38.5 months in prosthetic valve endocarditis, 26.8$\pm$31.2 months in paravalvualr leak, and 25.0$\pm$7.0 months in valve thrombosis. In bioprostheses, the intervals were in 102.0$\pm$23.9 months in the aortic valve, and 103.6$\pm$30.8 months in the mitral valve. The overall hospital mortality rate was 7.9% [17/26 : 15% in aortic valve reoperation [6/40 , 6.5% in reoperation on the mitral prostheses [9/135 and 5.7% in multiple valve replacement [2.35 . Low cardiac output syndrome was the most common cause of death [70.6% . Advanced New York Heart Association class [P=0.00298 , explant period [P=0.0031 , aortic cross-clamp time [P=0.0070 , prosthetic valve endocarditis [P=0.0101 , paravalvularr leak [P=0.0096 , and second reoperation [P=0.00036 were the independent risk factors, but age, sex, valve position and multiple valve replacement did not have any influence on operative mortality. Mean follow up period was 38.6$\pm$24.5 months and total patient follow up period was 633.3 patient year. Actuarial survival at 8 year was 97.3$\pm$3.0% and 5 year event-free survival was 80.0$\pm$13.7%. The surgical risk of reoperation on heart valve prostheses in the advanced NYHA class patients is higher, so reoperation before severe hemodynamic impairment occurs is recommended.

• Journal of Chest Surgery
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• v.19 no.4
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• pp.584-594
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• 1986

Despite the multivariate improvements in tissue treatment, material, and design of prosthetic heart valves in recent years, numerous complications that may lead to valve dysfunction remain a constant threat after valve replacement. Most common indications for prosthetic valve failure are primary valve failure, infective endocarditis, paravalvular leakage, and thromboembolism. From 1977 to 1986, 15 patients underwent reoperation for prosthetic valve failure in 278 cases of valve surgery. The etiology of prosthetic valve failure were primary valve failure in 12 patients [80 %], infective endocarditis in 2 patients [13.3 %], and a paravalvular leakage [6.7 %]. The average durations of implantation were 45.5 months; 53.9 months in primary valve failure, 16 months in infective endocarditis, and 4 months in paravalvular leakage. The rate of valve failure was high under age of 30 [11/15]. Calcifications and collagen disruption of prosthesis were main cause of primary valve failure in macro- & micropathology. Prosthesis used in reoperation were 5 tissue valves and 10 mechanical valves. Operative mortality were 13.3 % [2/15], due to intractable endocarditis and ventricular arrhythmia.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.858-863
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• 2004

In this study, the new prosthetic hand which can perform sensory feedback is developed. Although the continuous development of current prosthetic hands, they have some drawbacks. The drawbacks are the low grasping capabilities, the lack of sensory information given to the user, and so on. Despite the improvement of the function of fingers, the sensory information problem still remains undeveloped. By using differential gear and underactuated mechanical design, it can be solved with the minimum additional weight. And it will be applied to all of the prosthetic hands.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.10
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• pp.913-922
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• 2014

This paper describes design of a robotic above-knee prosthetic leg which is powered by electrical motors. As a special feature, the robotic prosthetic leg has enough D.O.F.s. For mimicking the human leg, the robotic prosthetic leg is composed of five joints. Three of them are called 'active joint' which is driven by electrical motors. They are placed at the knee-pitch-axis, the ankle-pitch-axis, and the an! kle-roll-axis. Every 'active joint' has enough torque capacity to overcome ground reaction forces for walking and is backlashless for accurate motion generation and high-performance balance control. Other two joints are called 'passive joint' which is activating by torsion spring. They are placed at the toe part and designed by Crank-rocker mechanism using kinematic design approach. In order to verify working performance of the robotic prosthetic leg, we designed a gait trajectory through motion capture technique and experimentally applied it to the robot.