• Imaging Science in Dentistry
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• 제44권3호
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• pp.213-220
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• 2014

Purpose: This study was performed to determine the efficacy of observers' prediction for the need of bone grafting and presence of perioperative complications on the basis of cone-beam computed tomography (CBCT) and panoramic radiographic (PAN) planning as compared to the surgical outcome. Materials and Methods: One hundred and eight partially edentulous patients with a need for implant rehabilitation were referred for preoperative imaging. Imaging consisted of PAN and CBCT images. Four observers carried out implant planning using PAN image datasets, and at least one month later, using CBCT image datasets. Based on their own planning, the observers assessed the need for bone graft augmentation as well as complication prediction. The implant length and diameter, the need for bone graft augmentation, and the occurrence of anatomical complications during planning and implant placement were statistically compared. Results: In the 108 patients, 365 implants were installed. Receiver operating characteristic analyses of both PAN and CBCT preoperative planning showed that CBCT performed better than PAN-based planning with respect to the need for bone graft augmentation and perioperative complications. The sensitivity and the specificity of CBCT for implant complications were 96.5% and 90.5%, respectively, and for bone graft augmentation, they were 95.2% and 96.3%, respectively. Significant differences were found between PAN-based planning and the surgery of posterior implant lengths. Conclusion: Our findings indicated that CBCT-based preoperative implant planning enabled treatment planning with a higher degree of prediction and agreement as compared to the surgical standard. In PAN-based surgery, the prediction of implant length was poor.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제35권6호
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• pp.381-389
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• 2013

Two patients with partial edentulous maxilla were scheduled to undergo installation of implant fixtures using a tooth-supported surgical template based on computer assisted treatment planning. After 3-dimensional (3D) computed tomographic scanning was transferred to the OnDemand3D (Cybermed Co., Seoul, Korea) software program for virtual planning, fixtures of MK III Groovy RP implant of the Br${\aa}$nemark System (Nobel Biocare AB Co., G$\ddot{o}$teborg, Sweden) was installed using the In2Guide (CyberMed Co., Seoul, Korea) tooth-supported surgical template with a Quick Guide Kit (Osstem Implant Co., Seoul, Korea) system in the posterior maxilla of each patient. Sinus floor elevation with a xenogenic bone graft procedure was also performed simultaneously in one patient. Fixture installations were completed successfully without complications, such as sinus mucosa perforation, bony bleedings, fenestrations, or others. During the last two-year follow-up period after prosthetics delivery, each implant was found to be fine with no other minor complications. The entire procedures are reported and the literatures on use of tooth-supported surgical template was reviewed.

• 대한장애인치과학회지
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• 제3권2호
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• pp.91-96
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• 2007

치과의사는 쇄골두개 이형성증의 특징에 대해 잘 알고 있어야 한다. 쇄골두개 이형성증 환자는 신체 및 정신적으로 특별한 이상을 보이지 않기 때문에, 영구치교환시기를 한참 지나 다수치아에서의 유치만기잔존 및 영구치의 미 맹출을 주소로 치과에 내원하게 되는 경우가 많은 것이 사실이다. 이런 의심이 들 때는 정확한 진단을 위해 반드시 다양한 방사선사진을 촬영해 보아야 하겠다. 또한 긴 치료기간으로 인해 환자의 협조와 여러 분야에 있어서 전문가들의 협력이 반드시 필요할 것이다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권3호
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• pp.254-261
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• 2009

저자들은 상악골 구치부에서 잔존 치조골의 흡수 및 상악동의 함기화로 인하여 통상적인 임플란트 시술이 어려운 증례에서 하악골의 하악지에서 자가골을 채취하여 이를 분쇄한 후 이종골과 부피비로 약1:1로 혼합하여 상악동 골이식술을 시행하고 동시에 임플란트를 식립하여 비교적 만족할만한 결과를 얻었기에 이를 문헌고찰과 함께 보고하며, 향후 이러한 증례들과 다른 골이식재를 사용한 증례들에 대하여 보다 장기적인 추적조사와 골이식된 부위의 골조직의 재형성, 식립된 임프란트의 보철적인 기능과 장기적인 예후에 대한 보다 체계적인 연구가 필요하리라 사료된다.

• 대한치과보철학회지
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• 제55권3호
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• pp.331-335
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• 2017

잔존 자연치의 발치가 필요한 환자에서 즉시의치의 제작을 고려해 볼 수 있다. 즉시의치를 장착함으로써 환자가 무치악으로 지내는 기간 없이 심미 및 기능을 회복해줄 수 있는 장점이 있지만 인상 채득이 어렵다는 점, 장착 후의 결과를 예측하기 어렵다는 단점이 있다. 본 증례에서는 잔존 자연치를 모두 발치해야 하는 49세 남환에서 캠퍼그나 트레이를 이용하여 최종 인상을 채득하고 수술용 형판을 이용하여 발치 및 치조골 성형술을 시행한 후, 즉시의치를 제작 및 장착하여 심미적, 기능적으로 만족할 만한 치료 결과를 보였기에 이를 보고하고자 한다.

• 대한치과보철학회지
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• 제54권3호
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• pp.246-252
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• 2016

이중관 가철성 국소의치는 지대치 간의 이차고정(secondary splinting), 응력의 수직 방향, 지대치 지렛점(fulcrum)의 내 외관 margin 부위 위치로 인한 지렛대 길이(the length of lever arm)의 감소로 소수 잔존치이거나 지대치의 상태가 좋지 않은 경우에도 성공적으로 사용될 수 있다. 또한 이중관(double crown)을 이용한 의치는 치아가 얼마 남지 않은 부분 무치악 환자 뿐만 아니라, 소수의 임플란트를 식립한 임플란트 오버덴처에 있어서 성공적인 치료결과를 보여주고 있다. 본 증례에서는 상악은 소수 치아가 잔존했고, 하악은 치조골 흡수 및 수축이 심하고 임플란트가 실패한 상태였다. 상악의 소수 잔존치는 치주적으로 불량하였고, 하악에는 2개의 임플란트만을 다시 식립하였다. 이러한 불리한 조건에서 이중관 가철성 국소의치를 이용한 치료를 계획하였다. 1년여 정도의 관찰 기간 동안 기능적, 심미적으로 만족스러운 결과를 얻을 수 있었으며, 이중관 가철성 국소의치의 효용성을 증명하였기에 본 증례를 보고하고자 한다.

• 대한치과보철학회지
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• 제54권3호
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• pp.259-266
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• 2016

하악 완전 무치악 환자의 보철수복에 있어 임플란트 식립 후 피개의치 제작은 첫 번째 치료 옵션으로 고려된다. 코너스 타입 부착장치를 이용한 피개의치는 견고한 지지를 제공하고 cross arch stabilization을 이루도록 하여 교합압을 균일하게 분산시키며, 의치에 의한 이차 고정으로 장기간의 안정성을 제공한다. 최근 소개된 팔라듐-은(Pd-Ag) 합금(Innovium)은 팔라듐, 은, 금 등의 귀금속 함량이 72% 이상인 CAD-CAM 시스템 전용 귀금속 합금으로 코너스 타입 부착장치를 제작하는데 적합한 물성을 가지고 있다. 본 증례에서는 완전 무치악 환자에서 상악에는 통상적인 총의치, 하악에는 임플란트를 4개 식립한 후에 코너스 타입 부착장치 피개의치 수복을 하였다. CAD-CAM 시스템을 이용하여 팔라듐-은 합금(Innovium)으로 제작된 코너스 타입 부착장치를 장착하였으며 이를 통해 의치의 유지와 안정을 향상시켰으며 만족할 만한 결과를 얻었기에 보고하고자 한다.

• 대한치과보철학회지
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• 제36권4호
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• pp.615-643
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• 1998

The purpose of this study was to evaluate the effect of cantilever length, load, and implant number on the stress distribution of implant supported fixed prosthesis. In the replica of an edentulous human mandible, four or five implants were placed and spaced evenly between the mental foramina and symmetrical gold alloy cast superstructures with cantilever were fabricated. Strain gauges were placed in buccal and lingual side of implants. 9, 15, 21kg of loads at varying cantilever lengths were applied to the occlusal surface of fixed prostheses. The strains were recorded from each gauge and principal stresses were calculated The results were as follows : 1. Increasing the length of the cantilever increased the stresses on the bone supporting implants. and the ratio of increase became high as increasing the load. 2. In the model with four implants, the highest compressive stress was measured on lingual side of the first implants nearest loading point and the highest tensile stress was measured on buccal side of the second implants. 3. In the model with five implants, the highest compressive stress was measured on lingual side of the first implants nearest loading point. And the highest tensile stress was measured on buccal side of the second implants, and lingual side of the third implants. 4. There was no significant change of the magnitude of stress on the most distal imp]ant of non cantilevered side as increasing the cantilever length or load. 5. In general, the superstructure supported by five implants reduced the stress and was less affected by cantilever length compared to the support provided by four implants.

• 대한치과보철학회지
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• 제43권3호
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• pp.322-330
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• 2005

Statement of problem. In distal extension removable partial denture, the preservation of health of abutment teeth is very important, but abutment teeth are subjected to unfavorable stress. Purpose. The purpose of this study was to investigate the biomechanical effects of mandibular removable partial dentures with various prosthetic designs using strain gauge analysis. Material and methods. Artificial teeth of both canines were anchored bilaterally in a mandibular edentulous model made of resin. Bilateral distal extension removable partial dentures with splinted and unsplinted abutments were fabricated. Group 1 : Clasp-retained mandibular removable partial denture with unsplinted abuhnents Group 2 : Clasp-retained mandibular removable partial denture with splinted abutments by 6-unit bridge Group 3 : Bar-retained mandibular removable partial denture Strain gauges were bonded on the labial plate of the mandibular resin model, approximately 2 mm close to the abutments. Two vertical experimental loadings (100N and 200N) were applied subsequently via two miniature load cells that were placed at mandibular first molar regions. Strain measurements were performed and simultaneously monitored from a computer connected to data acquisition system. For within-group evaluations, t-test was used to compare the strain values and for between-group comparisons, a one-way analysis of variance (ANOVA) was used and Duncan test was used as post hoc comparisons. Results. Strain values increased as the applied load increased from 100N to 200N for all groups (p<.05). The strain values of group 1 and 2 were tensile under loadings. In contrast, strain values of group 3 were compressive in nature. Under 100N loading, group 1 showed higher strain values than group 3 in absolute quantity (p<.05). Under 200N loading, group 3 showed higher strain values than group 1 and 2 in absolute quantity (p<.05). Group 1 showed higher strain values than group 2 (p<.05). Conclusion. Splinting of two isolated abutments by bridge reduced the peri-abutment strain in comparison with unsplinted abutments. Strain of bar-retained removable partial denture increased much more as applied load increased, but was compressive in nature.

• Journal of Periodontal and Implant Science
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• 제33권3호
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• pp.373-382
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• 2003

The successful use of osseointegrated implants to replace missing teeth has been demonstrated for both the completely and the partially edentulous patients. Many studies have confirmed an excellent long-term prognosis. The successful outcome of any implant procedure is surely dependent on the interrelationship of the various components that includes the following: biocompatibility of the implant material, macroscopic and microscopic nature of the implant surface, the status of the implant bed in both a health(noninfected) and a morphologic(bone quality) context, the surgical technique, the undisturbed healing phase, the subsequent prosthetic design, and long-term loading phase. Periodontally compromised patients have poor status of the implant bed and periodontal pathogen. No longitudinal data are available whether these factors affect the prognosis of implants. In this study, 102 machined $Br{{\aa}}nemark$ implants are inserted to analyze the success rate of 1-4 years and marginal bone loss in 49 chronic periodontitis patients. The following conclusions could be drawn from this study. 1. The cumulative success rate of implants at the 4-year of loading was 95.10%. 2. 5 failed implants have been removed. One implant have been removed due to infection, two implants were removed due to failure of osseointegration. and other two implants were removed due to mechanical failure caused by over-loading. 3. Mean marginal bone loss from the time of loading was 0.94mm at first year, 1.12mm at second year, 1.25mm at third year. These results suggest that implant therapy is good treatment modality in chronic periodontitis patients, and periodontal treatment including oral hygiene program is completed prior to insertion of implants.