• 대한치과보철학회지
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• 제19권1호
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• pp.39-45
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• 1981

Distal-extension removable partial dentures have long been implicated in the increase in mobility and the destruction of the supporting structures of the primary abutment teeth. Various clasping systems have traditionally been used to retain distal extension removable partial dentures, and other designs have been proposed to minimize torquing forces on the abutment teeth. Most recent studies investigating the effects of removable partial dentures on abutment teeth have been performed in it laboratory setting. Results obtained from in vitro research have given dentists insight into removable partial denture design, but laboratory test model cannot be constructed that simulates actual functional or parafunctiona1 movements and forces. The purpose of this study was to clinically evaluate the degree of tooth mobility produced by two clasping systems (suprabulge type and infrabulge type) used for distal extension removable partial dentures. Akers clasp and R.P.I. system were selected for the evaluation, and four patients required a distal extension removable partial denture on the mandibular arch were selected for participation in the study. Two partial dentures were constructed in the same condition expect the design of clasp. All abutments in the study were mandibular first or second premolars. Measurements of mobility were made with a research tool designed by $M\"{u}hlemann$. This instrument, periodontometer, measures tooth mobility in the mouth by means of a dial gauge accurated to 0.01mm when the tooth is stressed with a force meter. Lingual and buccal deflection of abutment tooth was measured using buccal and lingual pressure. The amount of force applied was 500gm. Tooth mobility tests were made at four key stages; 1. Before insertion of the first removable partial denture, baseline mobility was establsihed. 2. After wearing of the first prosthesis, measurement was made at weekly intervals for 4 weeks. 3. The removable partial denture was then taken from the patient, and tooth mobility was measured again at weekly intervals until the patient's established baseline mobility had returned. 4. The second prosthesis of different clasp design was worn for a month and evaluated in the same manner as the first. The sequence of placement of clasping system was alternated between patients. The following results were obtained from this study; 1. The mobility of abutment tooth increased during the initial stage of wear and returned to baseline mobility after removal of removable partial dentures. 2. The mobility of abutment tooth showed no difference between Akers clasp and I-bar clasp during the 4-week test period. 3. All teeth tested showed greater mobility toward the buccal than the lingual direction.

• 대한치과보철학회지
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• 제57권3호
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• pp.254-262
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• 2019

임플란트에 대한 급여의 확대로 임플란트의 지지를 받는 서베이드 고정성 보철물 제작 후 국소의치로 수복하는 증례에 대한 관심이 증가하고 있다. 이러한 증례의 예지성 있는 결과를 위해서 국소의치의 기본적인 설계 원칙과 잔존 치조골을 동시에 고려한 임플란트 계획수립이 필요하다. 본 증례는 편측 소수 잔존치를 가진 67세 남자 환자로 국민건강보험의 적용을 받을 수 있는 치료를 희망했다. CAD 소프트웨어를 활용하여 임시의치의 교합면, 국소의치의 기본적인 설계 원칙 및 흡수된 치조제를 모두 고려한 임플란트의 식립 위치를 결정하였다. 치료 결과 상악 및 하악 의치의 안정성 및 유지력이 적절하게 확보되었다. 본 증례는 임플란트 고정성 보철물 제작 시 국소의치의 기본적인 원칙과 흡수된 치조제를 모두 고려하기 위해 디지털 기술을 진단 및 치료에 활용하였고, 안정적인 결과를 얻었기에 이를 보고하고자 한다.

• 대한치과보철학회지
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• 제33권1호
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• pp.32-47
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• 1995

The purpose of this study was to determine the displacement of prosthesis & abutment and the stress distribution patterns induced in the periodontium by applying force to the fixed prosthesis. Two levels of periodontal support were compared using two-dimensional finite element stress analysis after placement of 3unit or 4 unit fixed partial denture(FPD) in case of missing of the lower first molar. Concentrated vertical load was delivered at the cusp tip of the second bicuspid or the central fossa of the pontic. The following results were obtained : 1. The greater the loss of alveolar bone in abutment teeth area, the greater the displacement of FPD and the stress concentration in alveolar bone around abutment. 2. The amount and direction of displacement and distribution of stress in the 4-unit FPD was better than those in the 3-unit FPD. 3. Multiple abutments reduced the amount of mesial and downward displacement of the weaked abutments and more uniformly distributed the stresses.

• 대한치과기공학회지
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• 제25권1호
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• pp.119-142
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• 2003

In the present work the knowledge of dental health as well as dental prosthesis has been studied on the basis of analysis of current dental prosthetic treatments for dental diseases prophylaxis and the final decision for dental prosthetic appliance. The results have been analyzed by the current dental health care and the subjective acknowledgement from 700 people of urban as well as rural inhabitance in our country. The results from the present work have been summarized as following: Depending dental status has been shown worse to be in the cases of divorce and bereavement, age and less educated or jobless. It is also interesting to note that the dental status has shown to be even worse than health status. It has been shown that the dental prosthetic treatments have been mainly caused by the oral disease (62.2%) and depend on the age and the educational level. According to the actual status of dental prosthetic treatments, the fixed partial denture was the most case (78.9%) that increased as divorced, bereavement and as less educated, less income, retired and jobless as well as from urban to rural. As a clinic for the dental prosthetic treatments, dental clinics have been most frequent visited as indicated by 59.6%, then the un-licensed dentist (6.5%), then the hospitals (3.7%), then the public health centers (2.2%). Most of those who are older in age, less educated and jobless have been treated by the un-licensed dentists. In point of view on the cost for dental prosthetic treatments, 93.1% have claimed to be too expensive, in as the divorced and the bereaved, the older age, the less educated and the jobless. About satisfaction of dental prosthetic treatments, 51.4% was satisfied, 39.4% was normal and 9.2% was dissatisfied. Most of people experienced increasing levels of satisfaction as their income increase. Most in the age range of 40-60 have wanted to be insured for the dental prosthetic treatments. It is also interesting to note that the older age and the less educated wanted to apply this kind of insurance.

• 대한치과보철학회지
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• 제33권4호
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• pp.807-823
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• 1995

The purpose of this study was to analyze the stress distribution and the displacement happened to the abutment, the prosthesis, and the surrounding structure according to the location of the nonrigid connector, that is, the keyway in the distal of canine and the mesial of the implant in the three unit fixed partial denture. Two-dimensional finite element model ws constructed and analyzed for the stress distribution and the displacement using software ABAQUS(Ver 5.2 Hibbitt, Karisson & Sorenson, Inc., 1992). After finishing the finite element model, the distribution load of 15kg was applied simultaneously to the all cusp tips of the prosthesis and the concentration load of 10㎏ was applied respectively at the each cusp tip of the prosthesis. The following results were obtained : 1. The amount of displacement of the implant was greater in case of the non-rigid connection than the rigid connection, and the more favorable displacement was shown in case of the IKb than the IKa. 2. Without regard to the connection method, the stress represented at the surrounding bone was similar, and the more favorabel stress distribution was shown in case of IKb. 3. The maximum stress was concentrated at the fastening screw and the neck of implant in all experimental groups, and their stress magnitudes were in the order of IKb, IR, and IKa.

• 대한치과보철학회지
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• 제34권3호
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• pp.632-649
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• 1996

The purpose of this study was to examine, by the method of 3-dimentional finite element analysis. how infraocclusion affected the stress distribution in surrounding bone and osseointegrated prosthesis. The 3-dimentional finite element mandibular models were made, in which the first and second molars were removed and the two osseointegrated implants were placed in the first and second molar sites and implant supported fixed prostheses were constructed. Analysis of equivalent stress and displacement induced by strong occlusion or infraocclusion was performed under vertical or inclined distributed loads. The results were as follows; 1. Under vertical load of 50N or 500N, the model in which infraocclusion had not been allowed showed greater stress on implants and the supporting bone than on natural teeth. 2. In the model in which infraocclusion of $30{\mu}m$ had been allowed, implant-prosthesis on the molars had no contact with opposing teeth under vertical load of 50N, However with the same allowed infraocclusion and the model under vertical load of 500N, implant prosthesis on the second molar had contact with opposing teeth, and stress distribution occured properly on natural teeth and implants. 3. Under $45^{\circ}$ inclined load, the model in which infraocclusion had not been allowed showed greater stress on implants and the supporting bone than on natural teeth. There was greater stress in the case of $45^{\circ}$ inclined load than in the case of vertical load. 4. Under $45^{\circ}$ inclined load of 50N or 500N, the model in which infraocclusion of $30{\mu}m$, had been allowed showed no occlusal contact on the implants and occlusal contact on the natural teeth. 5. In partially edentulous cases with implant supported prosthesis, we can prevent excessive load on implants by allowing infraocclusion.

• 대한치과보철학회지
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• 제60권4호
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• pp.382-394
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• 2022

심한 치주염을 가진 환자의 치료는 환자의 개개 치아의 정확한 진단과 전략적인 치료 계획을 통해 단계적으로 진행되어야 한다. 임플란트 지지 고정성 보철 수복은 국소의치에 비해 환자의 만족도가 높고, 안정적인 수직 고경을 유지할 수 있는 장점이 있지만, 경조직이 부족한 다수 치아 결손 부위에서는 심미적인 측면의 실패와 치료 기간이 길어진다는 점의 단점이 있을 수 있다. 또한 통상의 고정성 보철물을 제작하고 장착하는 데에는 일정 기간이 소요되는데, 이 기간 동안 임시 보철물은 치아의 기계적, 생물학적, 심미적 요구 조건을 만족시켜야 한다. 이번 증례 보고에서는 상악과 하악의 부분 무치악 환자에서 단계적인 접근을 통한 임플란트 고정성 보철물을 수복한 증례를 보고하고자 한다.

• 대한치과보철학회지
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• 제56권4호
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• pp.323-329
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• 2018

후방 무치악 부위를 수복하는데 있어서 선택할 수 있는 전통적인 치료방법으로는 가철성 국소의치와 임플란트 고정성 보철물이 있다. 최근, 환자의 전신 건강과 심미적 요구사항, 치료 비용, 잔존 치조골 상태 등을 고려하여, 두가지 치료가 결합된 임플란트 융합 국소의치(implant assisted RPD)개념이 이용되고 있다. 임플란트 융합 국소의치는 치조골 결손부가 큰 경우나, 생역학적으로 불리한 경우에 전통적인 가철성 국소의치보다 유지력과 안정성을 증진시킬 수 있으며 심미적이라는 장점이 있다. 또한 치조골 양이 상대적으로 많은 부위에 전략적으로 임플란트를 식립하여 전통적인 국소의치 디자인의 한계를 개선할 수 있을 뿐 아니라, 다수의 임플란트 식립을 통한 고정성 보철물에 비해 환자의 수술 부담을 줄여줄 수 있으며, 비용 절감 효과도 기대할 수 있다. 본 증례의 환자는 하악 양측 소구치부에 단일 임플란트를 식립하여, 임플란트 고정성 보철물을 지대치로 하는 양측성 후방연장 국소의치를 제작하여 치료를 진행하였다. 최종 보철물 장착 후 환자는 저작 기능 및 심미에 대해 만족도를 나타내었다. 이후 1년 이상 주기적인 관찰을 통해 예후를 관찰 중이다. 하악 부분 무치악 환자에서 임플란트를 이용한 가철성 국소의치 수복을 통해 증진된 지지와 안정을 얻었기에 이를 보고하는 바이다.

• Journal of Chest Surgery
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• 제17권4호
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• pp.753-761
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• 1984

Most patients having annuloaortic ectasia are associated with marked dilatation of the sinuses of Valsalva and the aortic annulus as well as the huge aneurysm of the ascending aorta. A 19 year old male patient complaining of tightness on left posterior chest wall underwent cardiac angiography in which demonstrated annuloaortic ectasia with ascending aortic aneurysm and aortic insufficiency. The patient had corrective operation replacing the ascending aorta and aortic valve with a composite graft[Dacron prosthesis containing a Bjork-Shiley aortic valve] within the aneurysmal sac. The coronary orifices were anastomosed to the tubular Dacron prosthesis [30 mm in diameter] by means of a second smaller Gore-Tex tube [8mm in diameter]. The aneurysmal sac was trimmed by removing the redundant wall and then wrapped outer wall of the Dacron prosthesis. Postoperatively, mediastinal bleeding was temporarily observed in the operative day and satisfactory blood pressure was maintained with small dose of dopamine. One week later, large amount of serous effusion was drained out of the retrosternal space making partial disruption of the skin which was healed well by daily local dressing. The patient discharged in good condition on postoperative 29th day with no residual complications and is doing very well on the 4 months follow-up.

• 대한치과의사협회지
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• 제49권6호
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• pp.334-339
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• 2011

The purpose of this study was to investigate the oral health condition and dental treatment need of low socioeconomic elderly people. A total of 116 elderly people who visited Boramae Hospital were evaluated with oral examination and panoramic radiogaph. The results showed that the most expecting treatment of low income aged people was removable partial denture. It was very clear in the age group of 70-84. In the age group under 70, most of the patients wanted prosthodontic tratement using fixed partial denture or crown. As the result of this study, elderly people with low socioeconomic status under age 85 needed removable partial denture or fixed prosthesis than complete denture. It is necessary to develop a more expanding and customized Senile prosthetic restoration program.