• 대한치과보철학회지
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• 제28권2호
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• pp.183-197
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• 1990

The purpose of this study was to analyse the magnitude and distribution of stresses using a Photoelastic model from and distal - extension removable partial dentures With four designed indirect retainers. The designs of the indirect retainers were as follows : Design No. 1 : Aker's clasp on 1st bicuspid with no indirect retainer. Design No. 2 : Aker's clasp on 1st bicuspid with indirect retainer on canine. Design No. 3 : Extension of the reciprocal arm of Aker's clasp toward incisal rest on canine. Design No. 4 : Connection with the indirect retainer as in No. 2 and extension of reciprocal arm of Aker' s clasp. A photoelastic model was made of the epoxy resin(PL - 1) and hardner(PLH - 1) and coated with plastic cement -1(PC -1) at the lingual surface of the epoxy model and set with chrome - cobalt partial dentures. A unilateral vertical load of 10kg to the right 1st molar and a vertical load of 10kg to the middle portion of the metal bar crossing both the 1st molars of the right and left, were applied. With the use of specially designed jig, fixture; loading device and the reflective circular polariscope, we obtained the following results : 1. When the unilateral vertical load and the vertical load of the middle portion of the metal bar were applied, design No. 2, 3 and 4 exhibited the higher stress concentration at the root apices and their surrounding tissues of the primary and secondary abutment teeth. 2. When the unilateral vertical load applied to design No. 2,3 and 4 the root apices of the primary and secondary abutment teeth and their surrounding tissues and the nonloaded side of edentulous area exhibited and even stress distribution. 3. When the vertical load was applied, the stress concentration fringe in the primary and secondary abutment teeth was in the order of No. 1,4,2 and 3. 4. No.1 and 4 exhibited the higher distrorted stress concentration at the primary teeth and the edentulous area in the nonloaded side. 5. No.2 design reduced the stresses at the apices of the alveoli of the primary abutment teeth bilaterally as well as on the crest of the residual ridge on the nonloaded side. 6. No. 2 design exhibited the most favorable stress distribution.

• 대한치과보철학회지
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• 제52권2호
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• pp.128-135
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• 2014

부분 무치악 환자는 고정성 보철, 가철성 국소의치, 임플란트 지지 고정성 보철로 수복될 수 있다. 그러나 소수 잔존치아만 남은 경우, 고정성 보철로는 수복이 어려우며, 국소의치 혹은 임플란트 지지 고정성 보철을 고려하게 된다. 이 경우 임플란트 지지 고정성 보철은 고정성 수복이라는 장점이 있으나, 충분한 개수의 임플란트가 식립되어야 하며, 환자의 전신적, 국소적 여건이 합당해야 하고, 경제적 부담도 크다. 가철성 국소의치는 지대치에 의한 대칭적인 지지가 중요하며, 특히 중심선에 대해 편측으로 소수 치아만 남은 경우에는 지점선에 대해 지대치에 유해한 스트레스를 가하면서 지대치의 예후가 불량해진다. 이 경우, 전략적 위치에 임플란트를 식립함으로써 임플란트를 의치의 유지 및 지지 요소로 활용하는 가철성보철물을 설계한다면 비용 대비 기능적이며 심미적인 보철 수복이 가능해진다. 본 두 증례는 상악 Kennedy Class I 부분 무치악 환자 중 편측으로 소수 잔존치가 전치에 국한하여 존재하는 경우로, 잔존치를 지대치로 사용하면서, 전략적 위치에 임플란트를 식립함으로써 의치의 지지가 향상된 국소의치를 제작한 증례이다.

• 대한치과보철학회지
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• 제51권3호
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• pp.214-220
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• 2013

무치악 환자의 임플란트 보철 치료는 지지, 유지, 안정성, 발음 등의 측면에서 더 우수한 결과를 보인다. 임플란트를 이용한 무치악 환자의 치료는 다양하며, 크게 가철성과 고정성으로 나눌 수 있다. 가철성 치료에는 임플란트 유지 및 지지 피개의치가 있으며, 고정성 보철치료에는 ceramo-metal 보철물과 임플란트 하이브리드 보철물(implant hybrid prosthesis)이있다. 치료계획의 수립은 잔존 치조제, 연조직, 악간 관계, 환자의 경제적 상황 등을 종합적으로 고려하여 수립해야 한다. 임플란트를 이용한 하이브리드 보철물은 고정성 치료를 통해 환자에게 적절한 교합력을 제공하고 심리적인 안정감을 주는 동시에 적절한 연조직의 회복을 통한 심미적인 결과를 얻을 수 있다. 본 증례는 73세 여환으로 상악 Kennedy Class I 부분 무치악과 하악 무치악 상태로 내원하였다. 상악에는 우측 견치부터 좌측 제1소구치까지 7개의 잔존치를 이용한 가철성 국소의치, 하악은 양측 측절치와 제1소구치 부위에 4개의 임플란트 고정체를 이용한 하이브리드 보철물로 최종 치료 진행하였으며 치료 후 기능적, 심미적으로 만족스러운 결과를 얻었기에 이를 보고하고자 한다.

• Journal of Periodontal and Implant Science
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• 제31권4호
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• pp.669-687
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• 2001

On the basis of the evidence that electrical stimulation could promote healing and regeneration of bone, this study was performed to investigate the effects of electrical stimulation on rat extraction socket, and to evaluate the potential of clinical application of electrical stimulation. Forty rats were used and divided into control groups(l0)and the experimental groups(30) in this study. The maxillary 1st molar were extracted in both groups. In experimental group, electrical stimulation was given at the current intensity of lmA(Test-1), l0mA(Test-2), 25mA(Test-3) each day. At 1,3,5,7 days after the tooth extraction, rats in both groups were serially sacrificed. And the specimens were prepared with Hematoxylin-Eosin stain for the light microscopic evaluation. The results of this study were as follows; 1. At 1 day after the extraction, the periodontal ligament was found in the extraction socket wall. The formation of blood clot with dense infiltration of inflammatory cells in control group and there were less inflammatory cells in test group. 2. At 3 day after the extraction, the cells and collagen of the periodontal ligament were so actively proliferated and synthesized that invaded into the connective tissue of the extraction sockets in the control group. There were the formation of new bone in the basal & lateral portion of socket wall in test -2 and -3. 3. At 5 days after the extraction, there were no formation of new bone in control group. But the more electrical stimulation was applied, the more formation of new bone in test group. 4. At 7 days after the extraction, the extraction sockets were almost filled with trabecular bone in each group. Bone maturarity was remarkable in test-3. 5. The electrical stimulation at l0mA and 25mA was more effective in the bone formation at 5 and 7 days after the extraction. From the above results, electrical stimulation could promote the extraction socket wound healing, and be utilized in the clinical application of the residual ridge expansion.

• 대한치과보철학회지
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• 제37권4호
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• pp.474-493
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• 1999

According to repeated measurements and correction procedures, the accuracy of the phase-shifting profilometry was developed. At first, after 20 final models for maxillary complete denture were duplicated , the mucosa sur-faces of models were measured with the phase-shifting proflometry and each mirror view of these was calibrated. Maxillary casts were divided into 4 groups of 5 casts per each, and wax dentures with 2 sheets of baseplate wax and artificial teeth were made and then cured according to the curing method of each group. Group I ; quick curing with QC-20 acrylic resin Group II ; 9 hour curing with QC-20 acrylic resin Group III ; SR-Ivocap system Group IV ; metal base and quick curing with QC-20 acrylic resin. After curing, polishing, and storing at $37^{\circ}C$ in saline for 30 days, the forms of the impression surface of the dentures were measured with the phase-shifting profilometry. Then, the impression surface form of each denture was placed in the optimal position of com-parison with the mirror view of the same final cast. The amount and direction of distortion of each denture was analyzed and the effects of polishing and storage in each denture were compared, The obtained results were as follows : 1. In Group I, the denture was observed as the appearance distorted in the opposite direction of the mucosa and the postero-lateral part of palatal portion of the denture was observed as the appearance separated from the mucosa. Also, the buccal flanges of the denture were observed as the appearance distorted in the direction of the mucosa. 2. In Group II, the postero-lateral part of palatal portion of the denture was observed as the appearance separated slightly from the mucosa. The bilateral buccal flanges of denture were observed as the appearance distorted severely in the direction of the mucosa. 3. In Group III the bilateral part of the residual ridge crest portions and the buccal flanges of the denture were observed as the appearance distorted in the direction of the mucosa, and specially, the buccal flanges of the maxillary tuberosities were distorted severely. 4. In Group IV, the acrylic resin base of the buccal portion of the denture was observed as the appearance distorted in the opposite direction of the mucosa. 5. The phase-shifting profilometry, done with repeated measurements and correction procedures, was effective in comparing the amount and direction of distortion at every position after the laboratory work and the delivery of maxillary complete denture.

• 대한치과보철학회지
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• 제55권1호
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• pp.61-70
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• 2017

본 증례에서는 기존의 총의치 사용 환자에서 의치의 이장된 인상면을 스캔하고 이를 삼차원적으로 반전하여 잔존 치조제의 형태를 재현하고, 의치에 방사선 불투과성 마커를 부착한 상태로 스캔 및 CT 촬영을 진행하여 스캔 이미지와 CT 영상이 중첩된 데이터 상에서 임플란트 식립을 계획하였다. 수술 당일에는 치은 형태에 맞게 제작된 맞춤형 지대주와 임시 수복물을 장착하였다. 임플란트 고정체의 골유착이 완료된 이후 최종 보철물을 제작하는 과정에서는 임플란트 식립 전 미리 스캔하여 저장된 임플란트 지대주 이미지 파일과 구강 내 지대주 상태에서 채득된 구강 스캔 이미지를 중첩하였다. 중첩을 통해 얻어진 정확한 지대주 형태 상에서 최종 보철물을 제작함으로써 최종 보철물의 변연 적합도를 높이고 임상 과정을 간소화 할 수 있었다.

• 대한치과보철학회지
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• 제39권5호
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• pp.556-575
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• 2001

For the improvement of denture fitness of changed residual ridge, denture liner can be used. Denture liner should be very stable physically in various environments of the mouth as well as be bonded strongly with denture resin. In this study. the specimens bonded with four kinds of soft denture liner and three kinds of hard denture liner were used to test the physical properties of the liners. All experimental groups were stored in $37{\pm}1^{\circ}C$ distilled water for 24hours, followed by thermocycling between $15^{\circ}C$ and $45^{\circ}C$ with 15 second dwell time. 1000, 2000, 3000 cycles of thermocycling were excuted and physical properties were measured by Instron Universal Testing Machine. The obtained results were as follows : 1. In tensile bond test of sea liners, it was shown that both of $Molloplast-B^{(R)}$ specimens before and after thermocycling had the highest tensile strength, and in case of hard liners, Dura-Liner $II^{(R)}$ specimen had the highest tensile strength before and after thermocycling. Depending on thermocycling, $Soft-Relining^{(R)}$, $Denture-Relining^{(R)}$, $Molloplast-B^{(R)}$, $Coe-Soft^{(R)}$ and $Kooliner^{(R)}$ specimen showed significant difference(p<0.05). 2. In strain test of soft liners, it was shown that $Molloplast-B^{(R)}$ specimen before thermocycling and the $Coe-Soft^{(R)}$ after thermocycling showed highest results, and in case of hard liners, the Dura-Liner $II^{(R)}$ specimen before and after thermocycling had the highest result. Depending on thormocycling, $Denture-Relining^{(R)}$, $Molloplast-B^{(R)}$ and Dura-Liner $II^{(R)}$ specimen showed significant difference(p<0.05). 3. In maximum distance test of soft liners. the $Molloplast-B^{(R)}$ specimen before thermocycling and the $Coe-Soft^{(R)}$ after thermocycling showed highest results. and in case of hard liners, the Dura-Liner $II^{(R)}$ specimen before and after thermocycling showed highest result. Depending on thermocycling, $Denture-Relining^{(R)}$, $Molloplast-B^{(R)}$ specimens showed significant difference(p<0.05). 4. In elasticity test of soft liners, the $Molloplast-B^{(R)}$ specimen before and after thermocycling showed highest result. and in case of hard liners, the Dura-Liner $II^{(R)}$ specimen before thermocycling and the $Tokuso-Rebase^{(R)}$ after thermocycling showed highest results. Depending on thermocycling, $Soft-Relining^{(R)}$ $Molloplast-B^{(R)}$ specimens showed significant difference (p<0.05).

• Journal of Periodontal and Implant Science
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• 제37권4호
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• pp.691-704
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• 2007

Between 1997 May and 2007 May, One hundred and seventeen patients were treated. There were 129 cases of sinus elevation using a lateral window opening procedure and 258 implants placed simultaneously or delayed. The cumulative survival rate of the implants calculated. The implants were evaluated according to surgical site, quality and quantity of bone, graft material, membrane used, the length and diameter of the implant and complications. 1. The 10-year cumulative survival rate of the implants by sinus augmentation using lateral window approach was 96.90%. 2. There was no difference in the survival rate between the implant placed simultaneously with sinus elevation (one stage) and the procedure performed in the delayed procedure (two stage). 3. There was no difference in the survival rate according to the type and amount of graft materials. 4. There was no difference in the survival rate according to the implant site, bone quality and quantity. 5. There was no difference in the survival rate when the $CollaTape^{(R)}$ or Gore-Tex was placed in the window of the lateral wall. 6. There was no difference in the survival rate of the implant length and diameter. 7. The survival rate was as low as 75.00% when there were more than two complications. Implant placement with sinus augmentation using the lateral window approach is a predictable treatment method. Although the vertical height of residual ridge is insufficient and the quality of bone is poor, the normal survival rate of the implants would be expected if an appropriate graft material and membrane is used with greater effort to prevent complications.

• 구강회복응용과학지
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• 제34권4호
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• pp.324-330
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• 2018

심하게 흡수된 치조제에서 안정적으로 유지될 수 있는 의치를 제작하기 위해서는 적절한 교합의 형성뿐만 아니라 주변근육 조직과의 조화를 고려한 적절한 연마면의 형성에 대한 고려가 필요하다. 중립대 인상 기법을 통해 기능하는 동안 혀, 볼, 입술에 대한 근신경계가 평형을 이루는 잠재적인 영역을 고려하여 인공치아를 배열하고, 연마면 형태가 동적인 근육의 해부학적 형태를 따르도록 할 수 있으며, 이는 의치의 안정과 유지 및 심미성을 향상시킬 수 있다. 본 증례는 심한 잔존 치조제의 흡수를 보이는 환자에게 중립대 개념을 적용하여 기능과 심미적인 측면에서 임상적으로 만족할 만한 결과를 얻었기에 이를 보고하고자 한다.

• 대한치과보철학회지
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• 제59권1호
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• pp.97-106
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• 2021

임플란트를 사용한 수복치료에서는 보철물을 위한 이상적인 위치에 임플란트가 식립되어야 한다. 치조골이 부족한 환자의 경우에는 최종 보철물을 위한 적절한 연조직 및 경조직 지지를 얻기 위해서 수술적인 처치를 포함한 구강내 처치를 필요로 하게 된다. CAD-CAM 기술을 활용한 보철물 설계는 위와 같은 수술적 처치의 필요성에 대해 임상가가 사전적으로 평가해볼 수 있는 청사진을 제시해준다. 본 증례에서는 CAD-CAM system을 통해 환자의 치료 전 구내상황, 수술적 처치에 대한 예상, 일련의 임시 보철물을 반영하여 최종 보철물을 계획하고 제작하였다. 최종 보철물을 반영하여 제작한 수술용 가이드를 사용하여 임플란트를 식립함과 동시에 치조골 증대술을 시행하였다. 이후 CAD-CAM을 활용하여, 맞춤형 지대주와 1차 및 2차 잠정 수복물을 디자인하고 제작하였으며, 환자의 구내에서 평가를 거친 2차 잠정 보철물과 동일한 형태의 최종 보철물을 제작하였다. 저작, 발음, 심미 기능에 있어서 환자와 술자 모두 만족할만한 결과를 얻을 수 있었다.