• 한국기계가공학회지
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• 제15권3호
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• pp.102-108
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• 2016

A dental ultrasonic surgical instrument, commercially known as a scaler, is a high-value-added advanced technology that is used for tartar removal, implant operations, and gum and jaw bone surgery. In this study, the piezoelectric phenomenon for making linear motion associated with input electrical signals was studied, and the behavior of the ultrasonic vibrator was investigated by using the commercially available finite element program ANSYS(R) for the purpose of designing dental surgery tools. Modal analysis was carried out, and the optimal frequency range was calculated from the analyzed results. The ultrasonic vibrator was then redesigned based on the calculated optimal frequency range. The performance of the system was tested, and consequently, the proposed methodology was proven useful in vibrator design.

• 한국유체기계학회 논문집
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• 제11권1호
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• pp.40-45
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• 2008

This paper proposes a tube pump composed of small-sized cams and followers for an implantable intrathecal drug infusion device. Each followers is driven by a cam and liquid is discharged by a sequential reciprocal motion of the followers. The advantage of this structure is that it allows the pump to be clean and valveless. To design a small-sized, low power pump some analysis were performed to determine the design parameters of the cam, follower and the tube. To verify the feasibility of the experiment, a prototype was manufactured and its operating characteristics were investigated. Experimental results were in accordance with the expected results obtained from analysis.

• 대한족부족관절학회지
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• 제19권1호
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• pp.1-6
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• 2015

Total ankle replacement has been performed for treatment of end stage arthritis of the ankle, hopefully being an alternative to ankle arthrodesis. However, due to its high failure rates, earlier versions of ankle replacements were not regarded as successful procedures. The latest design has shown increasingly positive results. Total joint replacement of the ankle itself is still regarded as a demanding procedure and much more challenging than that of the hip and knee in many aspects. Several studies, however, have pointed out that it is becoming the viable, accepted alternative for arthrodesis with advanced implants, appropriate patient selection, and proper training experience of procedures. Compared with arthrodesis, it shows equal or better outcomes in pain relief, range of motion, and patient's satisfaction. We are attempting to review its biomechanical characteristics, implant design, indications, complications, clinical outcomes, and survival rate.

• 구강회복응용과학지
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• 제37권3호
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• pp.130-137
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• 2021

목적: 다양한 봉합술을 통해 임플란트 주변에 최적화된 각화점막을 확보하려는 시도가 진행되었다. 본 연구의 목적은 임플란트 식립 후 2개의 서로 다른 봉합술 시행 후 연조직의 치유 양상을 평가하는 것이다. 연구 재료 및 방법: 15명의 환자에서 18개의 임플란트가 식립되었고 연구에 포함되었다. 부가적인 골이식 없이 단순 임플란트 식립만 진행하였다. 2개의 서로 다른 봉합술을 이용해 paramarginal flap design을 시행한 협측 판막을 임플란트 치유 지대주 하방으로 고정하였다. 디지털 구내 스캐너를 이용하여 초진, 수술 직후, 발사, 3개월 시점에 스캔을 진행하였다. 각 시점에 따른 스캔 데이터를 인접치의 교두, 소와, 치유지대주 등의 여러 점들을 기준으로 초진 데이터와 중첩하였다. 각 시점의 스캔 데이터를 초진 데이터와 subtraction한 다음 임플란트 주위 연조직의 증가량에 해당하는 폐곡면의 부피를 측정하였다. 폐곡면의 부피는 mm³ 단위로 계측하였다. 3개 시점에서 2개의 서로 다른 봉합술에 의한 부피 변화를 비교하기 위해 nonparametric rank-based 분석을 시행하였다. 결과: 양쪽 군 모두 치유는 양호하였다. 양쪽 봉합군은 수술 후 즉시 연조직 부피의 증가를 보여주었다. 3개월에 걸쳐 부피는 시간에 따라 유의성 있게 감소하였다(P < 0.001). Flap folding suture 군의 연조직 부피는 3개월 시점에서 interrupted suture 군보다 더욱 높은 중앙값을 보였으나 통계적 유의성은 없었다(P > 0.05). 결론: 임플란트 시행 시 paramarginal flap 형태로 거상된 판막을 flap folding suture로 고정한 군은 3개월 치유 기간 후 interrupted suture 군보다 더욱 높은 연조직 증강 수치를 보였다. 하지만 좀더 장기적인 관찰 연구가 필요할 것으로 사료된다.

• 한국전기전자재료학회논문지
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• 제17권9호
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• pp.911-915
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• 2004

In this study, the electrical characteristics of high-voltage LDMOSFET fabricated by the existing CMOS technology were investigated depending on its process and design parameter. In order to verify the experimental data, two-dimensional device simulation was carried out simultaneously. The off- state breakdown voltages of n-channel LDMOSFETs were increased nearly in proportional to the drift region length. For the case of decreasing n-well ion implant doses from $1.0\times{10}^{13}/cm^2$ to $1.0\times{10}^{12}/cm^2$, the off-state breakdown voltage was increased approximately two times. The on-resistance was also increased about 76 %. From 2-D simulation, the increase in the breakdown voltage was attributed to a reduction in the maximum electric field of LDMOS imolanted with low dose as well as to a shift toward n+ drain region. Moreover, the on- and off-state breakdown voltages were also linearly increased with increasing the channel to n-tub spacing due to the reduction of impact ionization at the drift region. The experimental and design data of these high-voltage LDMOS devices can widely applied to design smart power ICs with low-voltage CMOS control and high-voltage driving circuits on the same chip.

• 대한치과보철학회지
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• 제55권4호
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• pp.427-435
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• 2017

임플란트를 이용한 완전 무치악 환자의 치료에 있어 가장 중요한 것은 최종 보철물의 형태이며, 최종 보철물의 형태가 결정된 후 잔존골 분석 및 식립할 임플란트의 종류, 개수, 위치 등에 대한 선택이 이루어져야 한다. 본 증례는 상악 우측 측절치를 제외하고 전악에 임플란트가 식립된 채로 내원한 환자에 대해 고정성 보철 수복한 증례이다. 최종 보철물에 대한 고려 없이 임플란트가 식립되었기 때문에 먼저 총의치를 제작하여 안모 분석 및 고정성 보철 수복 가능성을 평가하였다. 고정성 보철 수복이 가능하다고 판단되어 진단 납형, 방사선 영상 및 디지털 분석을 통해 최종 보철물에 사용할 수 없는 임플란트를 치료계획에서 제외한 후 고정성 임시 보철물을 제작하였다. 4개월 동안 고정성 임시 보철물을 사용하면서 안정적인 교합과 심미적인 만족을 보였기에 CAD/CAM (Computer aided design and computer aided manufacturing)을 이용하여 지르코니아 최종 보철물로 이행하였고, 치료 종료 후 3개월 동안의 평가에서 만족스러운 결과를 얻었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1963-1966
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• 2005

Degenerative lumbar spinal stenosis(DLSS) is a disease inducing low back pain, leg pain, convulsion, numbness, and neurogenic claudication from compression of nerve root. Intervertebra fixation was reported to increase the degenerative of neighbor region after treatment. Recently, a new surgical technique of inserting a fixator between interspinous processes has been introduced. The purpose of this study is to design of the interspinous process fixator with flexibility to complement the trouble of using fixator in DLSS. This study evaluated the existing fixator through the mechanical test and modified fixators using the finite element analysis(FEA). Displacement, stiffness and Von-Mises stress were found to have similar values to those obtained from the mechanical test and the FEA in the biomechanical loading condition. Effects of variation in length and thickness were investigated to design an optimal fixator.

• 한국기계가공학회지
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• 제3권1호
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• pp.72-78
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• 2004

In this paper, mechanical behaviors of developed pedicle screw system, made of bio-mechanical materials(Ti-6Al-4V, Grade 5), ale predicted using FEM analysis. As a first step, morphologic construction of normal Korean spines and surgical operation convenience are considered to design optimum pedicle screw system. In this step, various design variables are considered as design parameters to develop optimized models. As a next step, tension and bending tests are performed to improve the structural performance of the developed system using finite element method. In this step, required Static compression and bending test specifications by ASTM F-04 25 04 01 are applied to understand the bio-mechanical behaviors of the designed spinal implant system under various load types. As the results of this research, it is possible to develop efficient pedicle screw system, having enough rigidity and fixation to stand any spinal damage under allowable stress conditions.

• 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.

• 한국IT서비스학회지
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• 제22권5호
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• pp.87-98
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• 2023

Traditionally, tooth restoration has been carried out by replicating teeth using plaster-based materials. However, recent technological advances have simplified the production process through the introduction of computer-aided design(CAD) systems. Nevertheless, dental restoration varies among individuals, and the skill level of dental technicians significantly influences the accuracy of the manufacturing process. To address this challenge, this paper proposes an approach to designing personalized tooth restorations using Generative Adversarial Network(GAN), a widely adopted technique in computer vision. The primary objective of this model is to create customized dental prosthesis for each patient by utilizing 3D data of the specific teeth to be treated and their corresponding opposite tooth. To achieve this, the 3D dental data is converted into a depth map format and used as input data for the GAN model. The proposed model leverages the network architecture of Pixel2Style2Pixel, which has demonstrated superior performance compared to existing models for image conversion and dental prosthesis generation. Furthermore, this approach holds promising potential for future advancements in dental and implant production.