A Study on the stress distribution of abutment teeth and residual ridge area between telescopic and clasp type rpd by fem method

학위논문(박사)--서울대학교 :치의학과 치과보철학 전공,1999.Docto

Postoperative pain control with ropivacaine following laparoscopic assisted vaginal hysterectomy: A randomized double blind study

Background: Although laparoscopic hysterectomy, a world popular technical method, ensures faster recovery and less post-operative pain rather than laparotomic hysterectomy, immediate postoperative pain control has been still required to improve a quality of postoperative care. We introduce an effective method, intraoperative injection of ropivacaine into both of uterosacral ligaments to control immediate postoperative pain. Materials and Methods: We performed a prospective, double-blind, and randomized study. We analyzed 40 cases of laparoscopic vaginal hysterectomy performed between July 2015 and November 2016, by a single surgeon (Y.S.Kwon). Enrolled patients were randomized into the ropivacaine injection group and the saline injection group. Before closure of the abdominal wall, 7.5% ropivacaine (5mL) or saline (5mL) was administered into both of uterosacral ligament. The primary outcomes included the post-operative pain intensity expressed by Numeric Ranking Scale (NRS) values at 2, 6, 12 and 24 hours after injection. The secondary outcomes included the amount of analgesics demanded for pain control during 24 hours after the surgery. Results: The pain intensity at 2 hours after injection was significantly lower in the ropivacaine injected group (p=.0234). There was no difference in pain intensity at 6, 12, and 24 hours after injection and the amount of analgesics used. However, the total amount of used opioid analgesic was lower in the ropivacaine injected group, as compared to the placebo injected group. (p=.0251). Conclusion: Intraoperative ropivacaine injection into both of uterosacral ligament during laparoscopic hysterectomy can reduce early post-operative pain and consumption of analgesics to improve a quality of postoperative care.Maste

RPD framework fabrication using computer-aided design (CAD) and rapid prototyping

CAD/CAM (computer-aided design/computer-aided manufacturing) 기술을 이용한 인레이 및 여러 고정성 보철물의 제작이 보편화되고 구강내 스캐너가 널리 보급되면서 디지털 치의학의 개념이 치과 보철학 분야 전반에 적용되고 있다. 그러나 가철성 보철 부분에서는 디지털 개념의 적용이 쉽지 않으며 기존의 주조 방식에 많이 의존하고 있다. 따라서 가철성 보철물의 제작 과정에 이런 개념을 적용해보려는 시도는 중요한 의미가 있다. 본 증례에서는 하악 Kennedy class III 무치악 환자에서 보철적, 심미적 요구에 의한 교합고경의 증가와 함께 CAD 및 쾌속조형술(RP, rapid prototyping)을 이용한 가철성 국소의치를 제작하였다. CAD를 이용하여 서베잉 및 국소의치 금속 구조물을 설계하였으며, 쾌속조형술은 금속 구조물을 주조하기 위한 레진 패턴 제작에 이용하였다. 9개월 간의 임상적 관찰 기간 동안 만족스러운 심미적, 기능적 결과를 얻어 이를 보고하고자 한다. Nowadays, digital dentistry is generally applied to prosthodontics with fabrication of inlays or any other fixed prostheses by utilizing CAD/CAM (computer-aided design/computer-aided manufacturing) technology and intraoral scanner. However, in fabricating removable prosthesis, there are some limitations for digital technology to substitute conventional casting method. Therefore, approaching removable prostheses fabrication with CAD/CAM technology would be a meaningful trial. In this case report, Kennedy class III mandibular edentulous patient who was in need of increasing the vertical dimension of occlusion was treated with removable partial denture using CAD and rapid prototyping technique. Surveying and designing the metal framework of the partial denture was performed with CAD, and sacrificial plastic pattern was fabricated with rapid prototyping technique. During the follow up period of nine months, the removable partial denture has provided satisfactory results in esthetics and function.OAIID:RECH_ACHV_DSTSH_NO:T201703437RECH_ACHV_FG:RR00200001ADJUST_YN:EMP_ID:A074391CITE_RATE:0DEPT_NM:치의학과EMAIL:[email protected]_YN:NN

Reuse Predicted Replication in Shared L2 Cache of CMPs

학위논문 (석사)-- 서울대학교 대학원 : 전기·컴퓨터공학부, 2012. 2. 전주식.반도체 집적 기술이 꾸준히 발달하면서 프로세서의 성능은 발전하였지만, 집적도의 증가에 따른 발열, 전력 소비 등의 문제로 단일 프로세서에서의 성능을 극대화 시키는 방법에서의 변화가 필요하게 되었다. 이에 멀티 프로세서 구조로 디자인의 변화가 있게 되었다. 하지만 프로세서 수의 증가가 성능 향상으로 직접적으로 이어지지 않음을 발견하고 이를 극대화할 수 있는 여러 방법이 소개되었다. 또한, 미래의 멀티 프로세서 디자인은 프로세서의 수뿐만 아니라 캐시의 용량도 함께 증가할 것으로 기대되기 때문에 늘어난 프로세서 수만 큼에 대한 성능 향상을 위한 여러 방법 중 캐시 관리 기법에 중점을 두어 연구를 진행하였다. 본 논문에서는 공유 L2 캐시 환경에서의 기존의 캐시 관리 기법 중 블록 복제 방법이 가지는 문제점을 분석하고 이를 보완하여 재사용 예측을 통해 블록을 복제하는 방법을 제안하였다. 그 결과 재사용 확률이 높은 양질의 블록만을 복제함으로써 외부 메모리 접근을 줄이고 지역 적중률을 높이는 효과를 확인할 수 있었다. 공유 L2 캐시 환경, 희생 복제 방법과 비교하여 각각 2.07%, 0.42% 성능 향상 효과를 얻을 수 있었다.As semi-conductor technology advances consistently, processors are becoming smaller and faster. However, several problems arise such as heat and energy consumption from an increase in degree of semi-conductor integration. This fact leads the changes in a methodological way in designing the single processor in a sense of maximizing performance, which results in the architecture of the multi-processor. However, the fact that an increase in the number of processors does not yield performance benefits in a linear manner has been found and a large number of techniques have been proposed to deal with this. The cache capacity in regards to future multi-processor design is expected to increase as well as the number of processors, which is where this paper intends to place a focus into. This paper proposes Reuse Predicted Replication (RPR) in shared L2 cache by analyzing and improving the problems of one of the cache management techniques. As a result, higher local hit rate as well as less off-chip memory access are verified by replicating quality replicas. RPR performs better by 2.07% and 0.42% over shared L2 cache environment and victim replication, respectively.Maste

일체형 지대주의 Diamond Like Carbon 표면 처리와 나사 조임 시기가 풀림 현상에 미치는 영향

본 연구의 목적은 내측연결형 임플랜트와 일체형 지대주를 사용하여 최종 보철물을 시적한 뒤에 5만 번의 반복하중 후에 다시 체결하고 20만 번의 반복하중을 가한 후의 지대주 풀림토크와 20만 번의 반복하중을 받은 지대주 풀림토크가 어떻게 달라지는지를 비교하고자 하는 것이다. 실험 재료로는 타이타늄 지대주와 DLC 코팅된 지대주를 사용하였다. 실험군은 4군으로 모두 8개의 ITI SLA 를 사용하였다. A군과 B군은 5만번, 20만번 반복하중을 가하고 Periotest값과 풀림 토크값을 측정하였으며 C군과 D군은 20만번 반복하중을 가하고 Periotest 값과 풀림토크값을 측정하였다. 풀림 토크값의 측정은 디지털 토크 게이지를 사용하였고, 반복하중은 MTS. (Bionix 850 II, MTS, U.S.A.)를 사용하였으며 100N/cm의 힘을 20도의 경사, 14Hz 의 조건으로 가하였다. A군과 C군은 코팅하지 않은 타이타늄 지대주를 사용하였으며, B군과 D군은 DLC 코팅한 지대주를 사용하였다. 1. 5만번 반복하중을 가한 뒤 측정한 풀림 토크는 B군에서 약간 더 큰 평균값을 보였다. 하지만 통계학적으로 두 군간에 유의한 차이를 보이지 않았다 (P>0.05). 2. 20만번 반복하중을 가한 뒤 측정한 최종 풀림 토크 값은 A군은 C군보다, B군은 D군보다 약간 더 큰 평균값을 보였으나 통계학적으로 두 군간에 유의한 차이를 보이지 않았다 (P>0.05). 3. 20만번 반복하중을 가한 최종 풀림 토크 값은 A, B군과 C, D군 사이에 통계학적으로 유의할 만한 차이가 없었다 (P>0.05). Statement of problem: It is difficult about assessing the loosening tendency of conical connection type implant after cyclic loading with diamond like carbon coating one-piece abutments, and also about the retightening effect. Purpose: This study was performed to investigate the influence of one-piece abutment screw retightening after cyclic loading and Diamond like coating Material and methods: Thirty two ITI implant were divided to 4 groups. Group 1,3-titanium abutment, group 2,4 - diamond like carbon coated abutment. Group 1,2 - cyclic loading after cyclic loading, Group 3,4- after Cyclic loading. After cyclic loading, periotest values were taken and removal torque values of abutments were measured with a digital torque gauge. Results: 1. The removal torque of group 2 after cyclic loading is slightly greater than the other groups but not significantly higher than others (P>0.05). 2. The final removal torque values after cyclic loading of group 1 is bigger than group 3, and group 2 is bigger than group 4, but not significantly higher (P>0.05). 3. The final removal torque values after cyclic loading of all groups are not significantly different (P>0.05)

THE INFLUENCE OF ABUTMENT SCREW TIGHTENING TIMING AND DLC COATING OF CONICAL CONNECTION IMPLANT SYSTEM

Statement of problem: It is difficult about assessing the loosening tendency of conical connection type implant after cyclic loading with diamond like carbon coating one-piece abutments, and also about the retightening effect. Purpose: This study was performed to investigate the influence of one-piece abutment screw retightening after cyclic loading and Diamond like coating Material and methods: Thirty two ITI implant were divided to 4 groups. Group 1,3-titanium abutment, group 2,4 - diamond like carbon coated abutment. Group 1,2 - cyclic loading after cyclic loading, Group 3,4- after Cyclic loading. After cyclic loading, periotest values were taken and removal torque values of abutments were measured with a digital torque gauge. Results: 1. The removal torque of group 2 after cyclic loading is slightly greater than the other groups but not significantly higher than others (P>0.05). 2. The final removal torque values after cyclic loading of group 1 is bigger than group 3, and group 2 is bigger than group 4, but not significantly higher (P>0.05). 3. The final removal torque values after cyclic loading of all groups are not significantly different (P>0.05)

의치상 레진의 세포독성에 관한 연구

The purpose of this study was to investigate the cytotoxicity and mutagenicity of denture base resins. According to manufacturer's instructions, resin specimens were made. Group 1 : heat-polymerizing acrylic resin (Luciton ) Group 2 : heat-polymerizing acrylic resin containing polyhedraloligosilsesquioxane(POSS resin) Group 3 : auto-polymerizing acrylic resin (Repair ) Group 4 : direct relining auto-polymerizing acrylic resin (Tokuso ). Fresh specimens 24 hrs. and 72 hrs. soaked specimens in distil)ed water were made. Responses with metabolic assay and mutagenesis assay to eluates from resin specimens were measured. Cultures with medium alone provided controls. Cytotoxicity was assessed with agar overlay test. The results were as follows; 1. Group 4 showed higher cytotoxicity than Group 1, Group 2 and Group 3 in fresh, 24-an4 72-hour immersion caries (p<.05). Group 3 showed higher cytotoxicity than Group 2 in fresh cases and showed higher cytotoxicity than Group 1 and Group 2 in 24-and 72-hour immersion cases (p<.05) . Group 1 and Group 2 showed no significant difference. 2. All acrylic denture base resins skewed significant increase of cell activity as immersion time increased (p<.05). 3. Auto-polymerizing acrylic denture base resins skewed higher cytotoxicity than heat-polymerizing acrylic denture base resins (p<.05). 4. All acrylic denture base resins showed lower mutagenicity than controls (p<.05)

삼차원 유한 요소법에 의한 가철성 국소의치 클래스프이 응력 분석

Statement of problem. In the partially edentulous patients, removable partial dentures have been working as a important treatment modality. Clasps, a kind of direct retainers, received some amount of stresses during the insertion and removal of partial denture on the abutment tooth. Purpose. The study is to investigate stresses of the different clasps. Material and methods. In order to investigate the degree of stresses, maxillary partial edentulism (Kennedy Class II modification I) was assumed and removable partial dentures were designed on it with three kinds of metallic materials; cobalt-chromium alloy, type IV gold alloy and commercially pure (c.p.) titanium. Aker's clasp was applied on the left second molar. RPA (mesial rest-proximal plate-Aker's) clasp was on the left first premolar and wrought wire clasp was on the right first premolar. Three dimensional, non-linear, dynamic finite element analysis method was run to solve this process. Results. 1. Cobalt-chromium alloy had the highest von Mises stress value and c.p. titanium had the lowest one irrespective of the types of clasps. 2. In the Aker's clasps, stress on the retentive tips was shown shortly after the appearance of stresses of the middle and minor connector areas. These time lag was much shorter in the RPA clasps than in the Aker's clasp. 3. In general. retentive tips of wrought wire clasps had much less amount of stress than other clasps. Conclusion. The amount of stress was the highest in the RPA clasp and the lowest in the wrought wire clasp, in general