• The Journal of the Korean dental association
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• v.50 no.5
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• pp.256-261
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• 2012

Temporomandibular joint (TMJ) prosthesis have been hesitated to use because of bitter memories about Proplast-Teflon interpositional TMJ implants. Many clinicians, however, are trying to use total TMJ prosthesis with getting continuous long-term follow-up results. Alloplastic total TMJ replacement have been applied to much more patients who have failed previous TMJ prostheses or TMJ implants, fibrous/bony ankylosis, severe osteoarthritis, degenerative joint disease, idiopathic condylar resorption, condyle loss by trauma or tumor resection, and other bony destructive diseases. Nowadays three types of total TMJ prosthesis are widely used. In this article, indications, types of prosthesis, safety and stability would be demonstrated with a case report.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.39
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• pp.6.1-6.6
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• 2017

Background: The purpose of this study is to evaluate the outcomes of four patients receiving stock Biomet TMJ prosthesis for reconstruction of the TMJs. Methods: TMJ reconstruction with stock Biomet TMJ prosthesis was performed in four patients who had joint damages by trauma, tumor, resorption, and ankylosis, which represent the indications of alloplastic prosthesis. Results: Loss of condyle from trauma and resorption of joint are good indications for prosthesis, but the patients should be informed about limitation of jaw movement. In case of structural damage of TMJ by tumor, tumor recurrence should be considered before planning TMJ reconstruction. Considering heterotopic bone formation in case of ankylosis, periodic follow-up and special surgical technique are required. Conclusions: Given careful treatment planning and understanding the functional limitation of TMJ prosthesis, alloplastic prosthesis is a safe and effective management option for the reconstruction of TMJs.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.4
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• pp.374-380
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• 2010

This paper proposes a wearable interface for a tendon-driven robotic hand prosthesis. The proposed interface is composed of a dataglove to measure finger and wrist joint angle, and a micro-control board with a wireless RF module. The interface is used for posture control of the robotic hand prosthesis. The measured joint angles by the dataglove are transferred to the main controller via the wireless module. The controller works for directly controlling the joint angle of the hand or for recognizing hand postures using a pattern recognition method such as LDA and k-NN. The recognized hand postures in this study are the paper, the rock, the scissors, the precision grasp, and the tip grasp. In experiments, we show the performances of the wearable interface including the pattern recognition method.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.244-244
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• 2000

We proposed the above-knee prosthesis using rotary MR damper in which knee joint is semi-actively controlled by microprocessor. Dissipation torque in the knee joint can be controlled by the magnetic field which is induced by applying current to a solenoid, Tracking control of knee joint angle was tested by 3-DOF Leg simulator. The experimental results show that the proposed above-knee prosthesis system had good performance in swing phase tracking and repetitive controller in conjunction with a computed control law and PD control law, reduced RMS tracking error as the repetitions of tracking. Moreover, desired knee angle trajectory was generated based on the estimation of gait period with the gyro signal and the tracking control was performed.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.6 no.2
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• pp.9-14
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• 2012

In this study, an advanced knee joint for active prosthesis leg driven by a linear actuator is suggested. The structure of knee joints of existing active prosthesis legs consists of three links. This kind of linkage requires large torque to drive the active prosthesis legs. Thus a new linkage structure is suggested to solve such problem in this paper. Motion characteristics of the suggested linkage are examined in the simulation. The motion simulation results show that the proposed linkage is able to imitate human gait cycles with the half of linear actuator speed in existing linkages.

• The Journal of Korea Robotics Society
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• v.11 no.4
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• pp.193-204
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• 2016

This paper presents an anthropomorphic finger prosthesis for amputees whose proximal phalanx is mutilated. The finger prosthesis to be proposed is able to make the amputees to perform the natural motion such as flexion/extension as well as self-adaptive grasping motion as if normal human finger does. The mechanism of finger prosthesis with three degrees-of-freedom (DOFs) consists of two five-bar and one four-bar linkages. Two passive components composed of torsional spring and mechanical stopper and only one active joint are employed in order to realize an underactuation. Each passive component is installed into the five-bar linkage. In order to activate the finger prosthesis, it is required for the user to flex and extend the remaining proximal phalanx on the metacarpophalangeal (MCP) joint, not an electric motor. Thus the finger prosthesis conducts not only the natural motion according to his/her intention but also the grasping motion through the deformation of springs by the object for human finger-like behavior. In order to reveal the operation principle of the proposed mechanism, kinematic analysis is performed for the linkage design. Finally both simulations and experiments are conducted in order to reveal the design feasibility of the proposed finger mechanism.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.39 no.6
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• pp.297-303
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• 2013

Alloplastic total replacement of the temporomandibular joint (TMJ) was developed in recent decades. In some conditions, previous studies suggested the rationale behind alloplastic TMJ replacement rather than reconstruction with autogenous grafts. Currently, three prosthetic products are available and approved by the US Food and Drug Administration. Among these products, customized prostheses are manufactured, via computer aided design/computer aided manufacturing (CAD/CAM) system for customized design; stock-type prostheses are provided in various sizes and shapes. In this report, two patients (a 50-year-old female who had undergone condylectomy for the treatment of osteochondroma extending to the cranial base on the left condyle, and a 21-year-old male diagnosed with left temporomandibular ankylosis) were treated using the alloplastic total replacement of TMJ using stock prosthesis. The follow-up results of a favorable one-year, short-term therapeutic outcome were obtained for the alloplastic total TMJ replacement using a stock-type prosthesis.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.2
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• pp.162-167
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• 2010

This is a case report about patient who had suffered from degenerative joint disease and treated by TMJ reconstruction with condylar prosthesis. The patient visited Korea University An-am hospital on 2007 complaining symptom about both TMJ pain, mouth opening limitation and open bite. From CT view there was severe resorption of both condylar head, therefore condylar prosthesis reconstruction was planned. After 3D RP model analysis for preparation, the patient was operated under general anesthesia for condylar prosthesis reconstruction and the symptom was alleviated. (increased mouth opening, reduced anterior open bite, full mouth occlusal contact achieved) Follow up was carried out monthly, but after this, patient refused follow up. After 26 months from the operation, the patient revisited for anterior open bite. In clinical evaluation, occlusal contact was remained, but anterior open bite was relapsed. From cephalometry analysis, severe resorption of glenoid fossa was found. Therefore, Autogenous disc reconstruction with alloplastic material was planned on August 2009. After another surgery, condylar prosthesis was regained its normal position in glenoid fossa, and occlusion was recovered properly.

• Journal of IKEEE
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• v.23 no.3
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• pp.883-892
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• 2019

This study is the method which is adapted to control ankle joint movement for resolving the problem of gait imbalance in intervals where gait environments are changed and slope walking, as applying terrain-adaptive technique to intelligent above-knee prosthesis. In this development of above-knee prosthesis, to classify the gait modes is essential. For distinguishing the stance phases and the swing phase depending on roads, a machine learning which combines decision tree and random forest from knee angle data and inertial sensor data, is proposed and adapted. By using this method, the ankle movement state of the prosthesis is controlled. This study verifies whether the problem is resolved through butterfly diagram.

• The Journal of the Korean bone and joint tumor society
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• v.3 no.1
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• pp.18-25
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• 1997

Prosthetic replacement is one of the most common methods of reconstruction after resection of malignant tumor around the knee. Gait analysis provides a relative objective data about the gait function of patients with prosthesis. The purpose of this study was to compare the gait pattern of the patients who underwent limb salvage surgery with prosthesis for distal femur and that of patients with prosthesis for proximal tibia. This study included ten patients (4 males, 6 females, mean age 22.7 years, range 14-36) who underwent a wide resection and Kotz hinged modular reconstruction prosthesis replacement and six normal adult(Control). The site of bone tumor was the distal femur (Group 1) in six patients and proximal tibia (Group 2) in 4 patients. The follow-up period ranged from 15 to 82 months (mean : 33 months). The evaluation consisted of clinical assessment, radiographic assessment, gait analysis using VICON 370 Motion Analysis System. The gait analysis included the linear parameters such as, walking velocity, cadence, step length, stride length, stance time, swing time, single support and double support time and the three-dimensional kinematics (joint rotation angle, velocity of joint rotation) of ankle, knee, hip and pelvis in sagittal, coronal and transverse plane. For the kinetic evaluation, the moment of force (unit: Nm/kg) and power (unit: Watt/kg) of ankle, knee and hip joint in sagittal, coronal and transverse plane. In the linear parameters, cadence, velocity, step time and single support were decreased in both group 1 and group 2 compared with control. Double support decreased in group 2 compared with control significantly(p<.05). In contrast to our hypothesis, there was no significant difference between group 1 and group 2. In Kinematics, we observed significant difference (p<.05) of decreased knee flexion in loading response (G2