• Structural Engineering and Mechanics
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• 제74권4호
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• pp.567-576
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• 2020

Considerable controversy surrounds the choice of the best abutment type for implant prosthetics. The two most common structures are hex and non-hex abutments. The non-hex abutment typically furnishes a larger contact area between itself and the implant than that provided by a hex structure. However, when a hex abutment is loaded, the position of its contact area may be deeper than that of a non-hex abutment. Hence, the purpose of this study is to determine the different biomechanical behaviors of an internal bone-level implant based on the abutment type-hex or non-hex-and clinical crown length under static and cyclic loadings using finite element analysis (FEA). The hex structure was found to increase the implant and abutment stability more than the nonhex structure among several criteria. The use of the hex structure resulted in a smaller volume of bone tissues being at risk of hypertrophy and fatigue failure. It also reduced micromovement (separation) between the implant components, which is significantly related to the pumping effect and possible inflammation. Both static and fatigue analyses, used to examine short- and long-term stability, demonstrated the advantages of the hex abutment over the non-hex type for the stability of the implant components. Moreover, although its impact was not as significant as that of the abutment type, a large crown-implant ratio (CIR) increased bone strain and stress in the implant components, particularly under oblique loading.

• 대한치과기공학회지
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• 제26권1호
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• pp.69-76
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• 2004

The objective of this finite element method study was to analyze the stress distribution induced on a supporting bone by 3.75mm, 4.0mm, 5.0mm diameter of dental implant fixture(13mm length). 3-dimensional finite element models of simplified gold alloy crown(7mm height) and dental implant structures(gold cylinder screw, gold cylinder, abutment screw, abutment, fixture and supporting bone(cortical bone, cancellous bone) designs were subjected to a simulated biting force of 100 N which was forced over occlusal plane of gold alloy crown vertically. Maximum von Mises stresses(MPa) under vertical loading were 9.693(3.75mm diameter of fixture), 8.885(4.0mm diameter of fixture), 6.301(5.0mm diameter of fixture) and the highest von Mises stresses of all models were concentrated in the surrounding crestal cortical bone. The wide diameter implant was the good choice for minimizing cortical bone-fixture interface stress.

• 대한구순구개열학회지
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• 제5권2호
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• pp.85-93
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• 2002

Simultaneous implant installation with bone graft was performed in 15 cases. Four cases were cleft alveolus patients. 56 implants were placed immediately with block bone grafts. 2 cases were cranial bone grafts and the others were iliac bone grafts. Three of 56 implants were lost(94.6% Survival rate). One of three was cleft alveolus case. The cleft alveolus patients with simultaneous implants installation showed functional and esthetic results without infraocclusion and positional changes. Bergland index was considered to be type I after 12 months later. Immediate implant installation with bone graft is one of choice of treatment in closing cleft alveolus hoping simultaneous implant installation could be related with function which might result in less resorption of graft. Functional and esthetic results are satisfaction ; there was no infraocclusion and positional changes.

• 한국치위생학회지
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• 제13권3호
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• pp.395-401
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• 2013

Objectives : The purpose of this research was to investigate the awareness of an adult on implants and the relevant factors which affect the satisfaction of a patient after an implant treatment. Methods : This study was conducted to 407 adult subjects in Seoul and Gyeonggi. A total of 384 data were analyzed except the questionnaires having poor responses or errors. Results : The acquaintance route of implant was TV advertisements, self-knowledge, internet, news, and newspapers. Dentist's ability to practice implant was the most important factor in patient's choice. The responents answered the expected lifespan of an implant was more than 5 years to 10 years. In terms of dental health management behavior on implants, the average response of the highest 4.07 points of 5 Likert scale. Generally women are more concerned with implant than men(p<0.01). The highly educated and elderly patients had tendency to receive more treatment(p<0.0001). Patients were more satisfactory after receiving regular checkups after treatment(p<0.05). The low expenses of implant satisfied the patients(p<0.05). Conclusions : As implant technology advances, the concern of patients on implants also increase. So reduction of cost can make the patients have access to the dentist and the patients' oral health must be improved through continuous dental care.

• Archives of Plastic Surgery
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• 제49권6호
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• pp.710-715
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• 2022

Background The latissimus musculocutaneous flap (LD flap) is a useful option for breast reconstruction following mastectomy. It has the advantage of obtaining sufficient tissue padding and natural shape by using autologous tissue. However, with the emergence of the skin-sparing mastectomy technique and artificial dermis matrix, direct-to-implant (DTI) breast reconstruction has become the first choice of surgery. The purpose of this study was to compare the satisfaction levels of patients who underwent DTI and LD flap with implant using patient-reported Breast-Q results. Methods A retrospective study was performed reviewing the records of 49 women who underwent immediate breast reconstruction with DTI or LD flap with implant and responded to the BREAST-Q questionnaire after the operation. The patient-reported breast-Q results were analyzed and correlated to the demographic information and intraoperative information. Results A total of 26 patients who underwent reconstruction with LD flap with implant and 23 patients with DTI were identified and responded to the questionnaire after an average of 32.3 and 10.4 months postoperation, respectively. According to the patient response to the breast-q values, satisfaction with breast was 60.0 and 57.0 points, psychosocial well-being 61.0 and 60.0 points, and sexual well-being 41.0 and 43.0 points in the two groups. Overall, there was no significant difference in the breastQ score between the two groups. Conclusion Patients who underwent DTI breast reconstruction seemed equally satisfied with the appearance and outcome of their breast reconstruction compared with LD flap with implant. Therefore, it appears that DTI is adequately replacing LD with implant.

• Journal of International Society for Simulation Surgery
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• 제4권1호
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• pp.13-16
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• 2017

Fibular free flap reconstruction is the flap of the choice in long-span mandibular bone reconstruction. The most common disadvantage of the fibular flap is short bone height to install dental implant. Double barrel fibular flap has been tried, however, bulky flap in the oral cavity hinder its use. Titanium reconstruction plate has been used simultaneously with the free fibular flap to stabilize occlusion and to fix the fibular flap. In this study, titanium reconstruction plate was fixed in the lower border of the mandible and the fibular free flap was fixed in the superior border of the titanium plate to improve implant-crown ratio. This new technique improved the longevity of the dental prosthodontics with dental implants.

• Journal of International Society for Simulation Surgery
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• 제1권1호
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• pp.13-15
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• 2014

Nowadays, with advanced 3D printing techniques, the custom-made implant can be manufactured for the patient. Especially in skull reconstruction, it is difficult to design the implant due to complicated geometry. In large defect, an autograft is inappropriate to cover the defect due to donor morbidity. We present the process of manufacturing the 3D custom-made implant for skull reconstruction. There was one patient with skull defect repaired using custom-made 3D titanium implant in the plastic and reconstructive surgery department. The patient had defect of the left parieto-temporal area after craniectomy due to traumatic subdural hematoma. Custom-made 3D titanium implants were manufactured by Medyssey Co., Ltd. using 3D CT data, Mimics software and an EBM (Electron Beam Melting) machine. The engineer and surgeon reviewed several different designs and simulated a mock surgery on 3D skull model. During the operation, the custom-made implant was fit to the defect properly without dead space. The operative site healed without any specific complications. In skull reconstruction, autograft has been the treatment of choice. However, it is not always available and depends on the size of defect and donor morbidity. As 3D printing technique has been advanced, it is useful to manufacture custom-made implant for skull reconstruction.

• 구강회복응용과학지
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• 제28권4호
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• pp.397-406
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• 2012

치아가 상실되면 주위 치조골의 개조와 흡수가 일어나면서 위축성 무치악을 초래하게 되고, 치은부착은 점차적으로 감소된다. 이에 따라 총의치의 지지력 감소, 저작 효율의 저하와 통증으로 인해 무치악 환자들은 의치 사용의 어려움을 경험한다. 이를 개선하기 위해 하악에 2개의 임플란트를 식립하고 어태치먼트를 장착하는 피개의치의 형태가 유지력 측면에서 바람직한 치료 방법으로 우선적으로 고려되고 있다. 본 증례는 오래된 상, 하악 무치악을 가진 환자로 하악에 2개의 임플란트를 식립하고, 상악은 총의치, 하악은 Locator$^{(R)}$ attachment를 이용한 임플란트 피개의치로 제작하였다. 본 증례에서 기능적, 심미적으로 만족스러운 결과를 얻었기에 수복 과정과 결과에 대하여 보고하고자 한다.

• Journal of Periodontal and Implant Science
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• 제48권6호
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• pp.373-382
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• 2018

Purpose: The aim of this study was to evaluate the effects of various prophylactic treatments of titanium implants on bacterial biofilm formation, correlating surface modifications with the biofilms produced by Pseudomonas aeruginosa PAO1, Staphylococcus aureus, and bacteria isolated from saliva. Methods: Pure titanium disks were treated with various prophylactic procedures, and atomic force microscopy (AFM) was used to determine the degree to which surface roughness was modified. To evaluate antibiofilm activity, we used P. aeruginosa PAO1, S. aureus, and saliva-isolated Streptococcus spp., Bacteroides fragilis, and Staphylococcus epidermidis. Results: AFM showed that the surface roughness increased after using the air-polishing device and ultrasonic scaler, while a significant reduction was observed after using a curette or polishing with Detartrine ZTM (DZ) abrasive paste. In addition, we only observed a significant (P<0.01) reduction in biofilm formation on the DZ-treated implant surfaces. Conclusion: In this study, both AFM and antibiofilm analyses indicated that using DZ abrasive paste could be considered as the prophylactic procedure of choice for managing peri-implant lesions and for therapy-resistant cases of periodontitis.

• 구강회복응용과학지
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• 제30권2호
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• pp.176-183
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• 2014

심하게 흡수된 치조제는 기능적인 하중을 견디기 어렵고 구강 조직의 유해 변화와 더불어 환자의 의치 적응을 어렵게 한다. 환자의 불편감을 해소하고 의치의 안정성과 유지력을 증가시키기 위해 임플란트를 이용한 피개의치가 치료 방법으로 선택될 수 있다. 로케이터 부착장치는 사용상의 편리성이 높으며 다양한 유지력을 갖는 남자부를 보유함으로써 임상에서 볼 형태 부착장치대용으로 많이 사용되고 있다. 본 증례는 77세 여자환자로서 낮은 수직고경과 심한 치조제 흡수를 보이는 상하악 무치악 상태였다. 이에 하악에 4개의 임플란트를 식립하고, 상악은 총의치, 하악은 로케이터 부착장치를 이용한 임플란트 피개의치로 수복하여 기능 및 심미적으로 만족할 만한 결과를 얻었기에 이를 보고하고자 한다.