• Structural Engineering and Mechanics
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• v.64 no.6
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• pp.819-826
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• 2017

The effects of thermocycling procedure and material shade on the mechanical properties and wear resistance of resin-based dental restorative materials are investigated. The modulus of elasticity, hardness, plasticity index and wear resistance are determined for the conventional composite, the nanohybrid composite and the nanofilled dental composites. Disc-shape samples are prepared from each material to investigate the effects of thermocycling procedure on the mechanical properties and wear resistance of different types of dental restorative materials. In this respect, a group of samples is thermocycled and the other group is stored in ambient conditions. Then nano-indentation and nano-scratch tests are performed on the samples to measure their mechanical properties and wear resistance. Results show that the A1E shade of the dental nanocomposite possesses higher modulus of elasticity and hardness values compared to the two other shades. According to the experimental results, the mean values for the modulus of elasticity and hardness of the A1E shade of the nanocomposite are 13.71 GPa and 1.08 GPa, respectively. The modulus of elasticity and hardness of the conventional dental composite increase around 30 percent in the oral environment due to the moisture and temperature changes. The wear resistance of the dental composites is also significantly affected by moisture and temperature changes in the oral conditions. It is observed that thermocycling has no significant effect on the hardness, plasticity index and wear resistance of the nanohybrid composite and the nanocomposite dental materials.

• The Journal of the Korean dental association
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• v.31 no.2 s.285
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• pp.137-143
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• 1993

• The Journal of the Korean dental association
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• v.39 no.5 s.384
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• pp.348-352
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• 2001

• The Journal of the Korean dental association
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• v.24 no.7 s.206
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• pp.593-603
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• 1986

Segmented Arch technique은 edgewise mechanics의 한 줄기로서, 미국 코네티컬 주립대학 교정과 과장인 Dr. Burstone에 의하여서 1950년대 이래로 꾸준히 개발되어온 생역학적인 개념(biomechanical concept)을 가장 효율적으로 치료에 적용하고자 함에 있다고 하겠다. 저자는 Segmented arch technique의 최근의 경향과 치료이론 및 술식을 다음의 순서로 4회에 걸쳐서 소개하고자 한다. 1. 전치의 Intrusion에 의한 과개교합의 치료법 -Deep Overbite Correction 2. Space closure - 수평방향의 치아이동방법 3. Root movement의 방법 - Torque mechanics 4. 구치를 Upright 시키는 방법 - Tip back mechanics.

• Imaging Science in Dentistry
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• v.52 no.2
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• pp.225-230
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• 2022

Purpose: This report presents the first known use of a rigid endoscope with augmented reality technology for the removal of an odontogenic cyst that penetrated the maxillary sinus and illustrates its practical use in a patient. Materials and Methods: In the preoperative period, cone-beam computed tomography was performed in a specially designed marker holder frame, and the contours of the cyst and the nearest anatomical formations were segmented in the 3D Slicer program. During the operation, a marker was installed on the patient's head, as well as on the tip of the endoscope, which made it possible to visualize the mass and the movement of the endoscope. The surgical intervention was performed with the support of augmented reality in HoloLens glasses (Microsoft Corporation, Redmond, WA, USA). Results: The use of this technology improved the accuracy of surgical manipulations, reduced operational risks, and shortened the time of surgery and the rehabilitation period. Conclusion: With the help of modern technologies, a navigation system was created that helped to track the position of the endoscope in mixed reality in real time, as well as to fully visualize anatomical formations.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.1
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• pp.72-77
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• 2014

3.2YSZ melted by the 'skull melting' method has good physical properties and does not undergo low-temperature degradation. Due to its excellent physical and mechanical properties, skull-melted 3.2YSZ has been developed as a dental implant material. In this study, a porous, resin-bonded diamond wheel was created and its grinding characteristics were compared with those of traditional nonporous wheels using skull-melted 3.2YSZ. The experimental results indicate that the porous, resin-bonded diamond wheel requires less grinding force and power. In addition, the porous, resin-bonded diamond wheel requires a greater degree of roughness.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.2
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• pp.49-54
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• 2014

Skull Melted 3.2YSZ has good physical properties and does not undergo low temperature degradation. Due to these excellent physical and mechanical properties, Skull Melted 3.2YSZ has been studied for use in dental implants. In this study, a ø2.2mm Initial Twist Drill was made using Skull Melted 3.2YSZ; the drilling characteristics were compared with those of the traditional SUS420J drill. The experimental results indicate that the Skull Melted 3.2YSZ drill requires similar thrust forces and has a slightly higher temperature.

• Journal of Technologic Dentistry
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• v.18 no.1
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• pp.39-65
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• 1996

The purpose of this to inquire of the people who run a dental mechanical laboratory having troubles to manage and to find out the reform measures on the point at issue. With having done random sampling for the chiefs of dental mechanical labs across the nation, and then marking the analysis of the data for the survey, I came to a conclusion to be as follow. 1. The operating problems in dental mechanical laboratory in Korea is that it is too near at hand that the requested days for the manufacture of dental prosthesis appliances form dental clinics(45%)(P<0.01) 2. The problem of dental mechanic manpower was due to a small salary and inferior working environment(35% each)(P<0.01) 3. Some of them discount dental mechanical charges in manufacturing dental prosthesis appliances(36.7%)(P<0.01) 4. Many of them employed unlicensed dental technicians(61.7%)(P<0.01) As a counterplan for the aforementioned, I think that the whole dental mechanics should cooperate in breaking off the customary custom to allow a discount on the dental mechanical charges and readjust the dental mechanical charge to a realistic level so as to contribute to the development of the dental mechanical community and the vetterment of the public oral hygience.

• The Journal of the Korean dental association
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• v.24 no.8 s.207
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• pp.698-702
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• 1986

Segmented Arch technique 은 edgewise mechanics의 한 줄기로서, 미국 코네티컬 주립대학 교정과 과장인 Dr. Burstone에 의하여 1950년대 이래로 꾸준히 개발되어온 치료술식으로서 그 특징을 한마디로 요약하면 생역학적인 개념(biomechanical concept)을 가장 효율적으로 치료에 적용하고자 함에 있다고 하겠다. 저자는 Segmented arch technique의 최근의 경향과 치료이론 및 술식을 다음의 순서로 4회에 걸쳐서 소개하고자 한다. 1. 전치의 Intrusion에 의한 과개교합의 치료법 -Deep Overbite Correction 2. Space closure - 수평방향의 치아이동방법 3. 치근의 이동방법 - Root movement 4. 구치를 Upright 시키는 방법 - Tip back mechanics

• The Journal of the Korean dental association
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• v.24 no.10 s.209
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• pp.870-876
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• 1986

Segmented Arch technique 은 edgewise mechanics의 한 줄기로서, 미국 코네티컬 주립대학 교정과 과장인 Dr. Burstone에 의하여 1950년대 이래로 꾸준히 개발되어온 치료술식으로서 그 특징을 한마디로 요약하면 생역학적인 개념(biomechanical concept)을 가장 효율적으로 치료에 적용하고자 함에 있다고 하겠다. 저자는 Segmented arch technique의 최근의 경향과 치료이론 및 술식을 다음의 순서로 4회에 걸쳐서 소개하고자 한다. 1. 전치의 Intrusion에 의한 과개교합의 치료법 -Deep Overbite Correction 2. Space closure - 수평방향의 치아이동방법 3. 치근의 이동방법 - Root movement 4. 구치를 Upright 시키는 방법 - Tip back mechanics