• The Journal of Korean Academy of Prosthodontics
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• v.50 no.4
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• pp.271-278
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• 2012

Purpose: Recently implant surgical guides were used for accurate and atraumatic operation. In this study, the accuracy of two different types of surgical guides, positioning device fabricated and stereolithography fabricated surgical guides, were evaluated in four different types of tooth loss models. Materials and methods: Surgical guides were fabricated with stereolithography and positioning device respectively. Implants were placed on 40 models using the two different types of surgical guides. The fitness of the surgical guides was evaluated by measuring the gap between the surgical guide and the model. The accuracy of surgical guide was evaluated on a pre- and post-surgical CT image fusion. Results: The gap between the surgical guide and the model was $1.4{\pm}0.3mm$ and $0.4{\pm}0.3mm$ for the stereolithography and positioning device surgical guide, respectively. The stereolithography showed mesiodistal angular deviation of $3.9{\pm}1.6^{\circ}$, buccolingual angular deviation of $2.7{\pm}1.5^{\circ}$ and vertical deviation of $1.9{\pm}0.9mm$, whereas the positioning device showed mesiodistal angular deviation of $0.7{\pm}0.3^{\circ}$, buccolingual angular deviation of $0.3{\pm}0.2^{\circ}$ and vertical deviation of $0.4{\pm}0.2mm$. The differences were statistically significant between the two groups (P<.05). Conclusion: The laboratory fabricated surgical guides using a positioning device allow implant placement more accurately than the stereolithography surgical guides in dental clinic.

• Journal of Chest Surgery
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• v.46 no.2
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• pp.135-137
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• 2013

An atrial septal defect is the most common type of congenital heart disease among adults. Surgical repair or percutaneous closure of the defect is the treatment options. Even though percutaneous closure seems to be less risky than surgical repair, it may result in fatal complications like device embolism, cardiac perforation and tamponade. Herein we report a case of the embolism of a device into the pulmonary artery after one hour of percutaneous closure in which the embolized device was surgically removed and the defect was closed with a pericardial patch.

• Journal of Biomedical Engineering Research
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• v.43 no.6
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• pp.382-389
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• 2022

In this study, the accuracy of the orthognathic surgical guides with single-stage split path was upgraded to realize orthognathic surgical guides with two-stage split path and simulated surgery was performed to verify its accuracy. As a result, the average error distance between the simulation model and the scan model was + 0.289 / - 0.468 mm (standard deviation 0.128), which was confirmed to be within ± 0.5 mm, which is a clinically acceptable level. Also, there was no significant difference compared with the average value of + 0.313 / - 0.456 mm (average standard deviation 0.106) of the conventional single-stage split path type device. It is judged that the use of this device can contribute to the reduction of surgical time and increase in accuracy since a separate finishing operation for bone preparation is unnecessary.

• The Journal of Korea Robotics Society
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• v.9 no.1
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• pp.48-56
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• 2014

In robotic surgery, a surgeon checks only a surgical site of patient in the progress of surgery by vision and sound information. In order to solve this limited information, the haptic function is necessary. And haptic surgical robot is also necessary to design a haptic master device. The master device for laparoscope operation with cable-conduit was developed in previous research to give haptic function. It suggested a possibility of developing a master device by using the cable-conduit. However, it is very inconvenient to use. Therefore, this paper suggests a new mechanism design structure to solve the problems of the previous work by new forming a new master device. And it has proved that it's usability is better than previous one. Furthermore it has also experimented and analyzed that a backlash of new master device is compensated by smooth backlash inverse algorithm.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.32.1-32.4
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• 2020

Background: Le Fort I osteotomy is a highly effective treatment for skeletal jaw deformities and is commonly performed. High Le Fort I osteotomy is a modified surgical procedure performed for improving the depression of the cheeks by setting the osteotomy higher than the conventional Le Fort I osteotomy. Developments in three-dimensional (3D) technology have popularized the use of 3D printers in various institutions, especially in orthognathic surgeries. In this study, we report a safe and inexpensive method of performing a high Le Fort I osteotomy using a novel 3D device and piezosurgery, which prevent tooth root injury without disturbing the operation field for patients with a short midface and long tooth roots. Results: A 17-year-old woman presented with facial asymmetry, mandibular protrusion, a short midface, and long tooth roots. We planned high Le Fort I osteotomy and bilateral sagittal split ramus osteotomy. Prevention of damage to the roots of the teeth and the infraorbital nerve and accurate determination of the posterior osteotomy line were crucial for clinical success. Le Fort I osteotomy using 3D devices has been reported previously but were particularly large in size for this case. Additionally, setting the fixing screw of the device was difficult, because of the risk of damage to the roots of the teeth. Therefore, a different surgical technique, other than the conventional Le Fort I osteotomy and 3D device, was required. The left and right parts of the 3D device were fabricated separately, to prevent any interference in the surgical field. Further, the 3D device was designed to accurately cover the bone surface from the piriform aperture to the infra-zygomatic crest with two fixation points (the anterior nasal spine and the piriform aperture), which ensured stabilization of the 3D device. The device is thin and does not interfere with the surgical field. Safe and accurate surgical performance is possible using this device and piezosurgery. The roots of the teeth and the infraorbital nerve were unharmed during the surgery. Conclusions: This device is considerably smaller than conventional devices and is a simple, low-cost, and efficient method for performing accurate high Le Fort I osteotomy.

• ETRI Journal
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• v.39 no.1
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• pp.87-96
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• 2017

Ultrasonic surgical devices are routinely used for surgical procedures. The incision and coagulation of tissue generate a temperature of $40^{\circ}C-150^{\circ}C$ and depend on the controllable output power level of the surgical device. Recently, research on the classification of grasped tissues to automatically control the power level was published. However, this research did not consider the specific characteristics of the surgical device, tissue denaturalization, and so on. Therefore, this research proposes a robust algorithm that simulates noise to resemble real situations and classifies tissue using conventional classifier algorithms. In this research, the bioimpedance spectrum for six tissues (liver, large intestine, kidney, lung, muscle, and fat) is measured, and five classifier algorithms are used. A signal-to-noise ratio of additive white Gaussian noise diversifies the testing sets, and as a result, each classifier's performance exhibits a difference. The k-nearest neighbors algorithm shows the highest classification rate of 92.09% (p < 0.01) and a standard deviation of 1.92%, which confirms high reproducibility.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.3
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• pp.178-185
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• 2015

Purpose: The purpose of this study was to conduct a comparative assessment on the satisfaction level for the two interfaces of surgical guide system (SimPlant and R2GATE), the design and convenience of manufactured surgical guides and the importance of using the surgical guides thereof by means of survey. Materials and Methods: Hereupon, they simulated the implant surgical process by mounting the two manufactured systems of surgical guide on a dental mold, respectively. The study subjects were instructed to complete the questionnaire as to the satisfaction level upon completion of the simulated surgery. This study summarized the data of each question after collecting the completed questionnaires. Then, this study analyzed the summarized data by utilizing statistical program SPSS 20.0 (IBM). Results: R2GATE had a higher value of the satisfaction level on the design and convenience of manufactures surgical guides. R2GATE group ($7.33{\pm}1.26$) was found to have a higher value in terms of the overall satisfaction level compared to SimPlant group ($6.67{\pm}1.26$) (${\alpha}$ = 0.05). Conclusion: The user satisfaction level on the surgical guide manufactured for R2GATE system was to such an extent as it can be widely used in clinical environment. Moreover, the surgical guide manufactured as R2GATE system can guide both the length and direction of a drill simultaneously. As a result, it is highly recommended for those beginners who do not have a lot of experience in implant placement.

• Journal of Chest Surgery
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• v.45 no.5
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• pp.320-322
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• 2012

The percutaneous transcatheter closure of secundum atrial septal defect has recently become an increasingly widespread alternative to surgical closure in many centers. Although immediate, short, and intermediate term results of percutaneous transcatheter septal closure are promising, the procedure is not free from inherent complications that could be lethal. We report a case of device embolization necessitating emergent surgical retrieval.

• Clinical and Experimental Pediatrics
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• v.50 no.5
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• pp.469-475
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• 2007

Purpose : This study was performed to compare the safety, efficacy and clinical results of the Amplatzer septal occluder (ASO) for closure of secundum atrial septal defect (ASD) with surgery. Methods : One hundred fifteen patients diagnosed as isolated secundum ASD in Gil Medical Center, Gachon University of Medicine from January 2000 to July 2006 were included. Seventy patients underwent surgical repair of ostium secundum ASD. Forty-five consecutive patients were treated with percutaneous closure using ASO. We compared the mortality, morbidity, hospital stay, and efficacy between two groups. Results : Male to female ratio was 1:2.4. The mean age and the size of defects were not statistically different. No mortality occurred in either group. The success rate was 97.8% in the device group and 100% in the surgical group. The overall rate of complications was higher in the surgical group than in the device group (64.0 vs. 15.6%, P<0.05). Hospital stay was shorter in the device group than in the surgical group ($4.2{\pm}1.2$ vs. $12.4{\pm}4.7days$, P<0.0001). Residual shunt rates were more frequent in the device group (8.9%) than in the surgical group (4.3%) at discharge. All residual shunts disappeared at 3 months follow-up. Conclusion : Percutaneous closure of ASD using ASO is a safe and effective alternative to surgical repair. The indications of percutaneous ASD closure with ASO would be expanded by accumulation of experiences and evolutions of device.

• KIPS Transactions on Software and Data Engineering
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• v.12 no.6
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• pp.275-284
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• 2023

Virtual reality simulations are used for education and training in various fields, and are especially widely used in the medical field recently. The education/training simulator consists of tactile/force feedback generation and image/sound output hardware that provides a sense similar to a doctor's treatment of a real patient using real surgical tools, and software that produces realistic images and tactile feedback. Existing simulators are complicated and expensive because they have to use various types of hardware to simulate various surgical instruments used during surgery. In this paper, we propose a dental surgical simulation system using a force feedback device and a morphable haptic controller. Haptic hardware determines whether the surgical tool collides with the surgical site and provides a sense of resistance and vibration. In particular, haptic controllers that can be deformed, such as length changes and bending, can express various senses felt depending on the shape of various surgical tools. When the user manipulates the haptic feedback device, events such as movement of the haptic feedback device or button clicks are delivered to the simulation system, resulting in interaction between dental surgical tools and oral internal models, and thus haptic feedback is delivered to the haptic feedback device. Using these basic techniques, we provide a realistic training experience of impacted wisdom tooth extraction surgery, a representative dental surgery technique, in a virtual environment represented by sophisticated three-dimensional models.