• The Journal of Advanced Prosthodontics
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• 제8권2호
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• pp.150-157
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• 2016

PURPOSE. The modified lateral-screw-retained implant prosthesis (LSP) is designed to combine the advantages of screw- and cement-retained implant prostheses. This retrospective study evaluated the mechanical and biological complication rates of implant-supported single crowns (ISSCs) inserted with the modified LSP in the posterior region, and determined how these complication rates are affected by clinical factors. MATERIALS AND METHODS. Mechanical complications (i.e., lateral screw loosening [LSL], abutment screw loosening, lateral screw fracture, and ceramic fracture) and biological complications (i.e., peri-implant mucositis [PM] and peri-implantitis) were identified from the patients' treatment records, clinical photographs, periapical radiographs, panoramic radiographs, and clinical indices. The correlations between complication rates and the following clinical factors were determined: gender, age, position in the jaw, placement location, functional duration, clinical crown-to-implant length ratio, crown height space, and the use of a submerged or nonsubmerged placement procedure. RESULTS. Mechanical and biological complications were present in 25 of 73 ISSCs with the modified LSP. LSL (n=11) and PM (n=11) were the most common complications. The incidence of mechanical complications was significantly related to gender (P=.018). The other clinical factors were not significantly associated with mechanical and biological complication rates. CONCLUSION. Within the limitations of this study, the incidence of mechanical and biological complications in the posterior region was similar for both modified LSP and conventional implant prosthetic systems. In addition, the modified LSP is amenable to maintenance care, which facilitates the prevention and treatment of mechanical and biological complications.

• Journal of Korean Dental Science
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• 제6권1호
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• pp.27-33
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• 2013

The introduction of osseointegrated dental implants in dentistry brought about a new era in everyday dental practice. For the past 50 years, prosthetic restoration with implant-supported prosthesis has developed into a viable and predictable treatment option. Alongside the increasing use of dental implants is the occurrence of many complications during implant placement (surgery), in the mechanical or prosthetic problem, and in the biological aspect. In particular, abutment or screw fracture as one of the mechanical complications can put the dentist in a tight spot in a clinical situation. It is hard to remove the fractured abutment and screw to restore it properly. Therefore, it is very important that clinicians consider possible complications in advance and make an appropriate treatment plan. We discuss cases of abutment fracture and mechanical/prosthetic complications together with the causes and solutions.

• The Journal of Advanced Prosthodontics
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• 제8권6호
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• pp.494-503
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• 2016

PURPOSE. The aim of this study was to compare the efficacies of two-implant splinting (2-IS) and single-implant restoration (1-IR) in the first and second molar regions over a mean functional loading period (FLP) of 40 months, and to propose the appropriate clinical considerations for the splinting technique. MATERIALS AND METHODS. The following clinical factors were examined in the 1-IR and 2-IS groups based on the total hospital records of the patients: sex, mean age, implant location, FLP, bone grafting, clinical crown-implant ratio, crown height space, and horizontal distance. The mechanical complications [i.e., screw loosening (SL), screw fracture, crown fracture, and repeated SL] and biological complications [i.e., peri-implant mucositis (PM) and peri-implantitis (PI)] were also evaluated for each patient. In analysis of two groups, the chi-square test and Student's t-test were used to identify the relationship between clinical factors and complication rates. The optimal cutoff value for the FLP based on complications was evaluated using receiver operating characteristics analysis. RESULTS. In total, 234 patients with 408 implants that had been placed during 2005 - 2014 were investigated. The incident rates of SL (P<.001), PM (P=.002), and PI (P=.046) differed significantly between the 1-IR and 2-IS groups. The FLP was the only meaningful clinical factor for mechanical and biological complication rates in 2-IS. CONCLUSION. The mechanical complication rates were lower for 2-IS than for 1-IR, while the biological complication rates were higher for 2-IS. FLP of 39.80 and 46.57 months were the reference follow-up periods for preventing biological and mechanical complications, respectively.

• Journal of Korean Neurosurgical Society
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• 제46권3호
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• pp.226-231
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• 2009

Objective : We describe our clinical experiences and outcomes in patients who had thromboembolic complications occurring during endovascular treatment of intracerebral aneurysms with a review of the literature. The types of thromboembolic complications were divided and the treatment modalities for each type were described. Methods : Between August 2004 and March 2009 we performed endovascular embolization with Guglielmi detachable coils for 173 patients with 189 cerebral aneurysms, including ruptured and unruptured aneurysms at our hospital. Sixty-eight patients were males and 105 patients were females. The age of patients ranged from 22-82 years (average, 58.8 years). We retrospectively evaluated this group with regard to complication rates and outcomes. The types of thromboembolic complications were classified into the following three categories: mechanical obstruction, distal embolic stroke, and stent-induced complications, which corresponded to types I, II, and III, respectively. A comparison of the clinical results was made for each type of complication. Results : Only eight patients had a thromboembolic complication during or after a procedure (4.6%). Of the eight patients, two had a mechanical obstruction as the causative factor; the other three patients had distal embolic stroke as the causative factor. The remaining three patients had stent-induced complications. In cases of mechanical obstruction, recanalization occurred due to the use of intra-arterial thrombolytic agents in one of two patients. Nevertheless, a poor prognosis was seen. In the cases of stent-induced complications, in one of three patients in whom a thrombus developed following stent insertion, a middle cerebral artery territory infarct developed with a poor prognosis despite the use of wiring and an intra-arterial thrombolytic agent. In the cases of distal embolic stroke, all three patients achieved good results following the use of antiplatelet agents. Conclusion : Treatment for thromboemboic complications due to mechanical obstruction and stent-induced complications include antiplatelet and intra-arterial thrombolytic agents; however, this cannot guarantee a sufficient extent of effectiveness. Therefore, active treatments, such as balloon angioplasty, stent insertion, and clot extraction, are helpful.

• Journal of Chest Surgery
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• 제27권12호
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• pp.1031-1035
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• 1994

Mechanical valve thrombosis is a serious and potential lethal complication unless early diagnosis & prompt therapy are made. We have been experienced 3 cases of valve thrombosis. From Aug. 1988 to July 1994, reoperations of mitral valve replacement [MVR] with mechanical prostheses [all mitral] were performed in three patients[2 men, 1 woman] due to valve thromboses. All three patients were diagnosed by means of cineradiography. Preoperative status of was shock status and he was applied intra-aortic balloon pump [IABP]. All three cases of prosthetic valve failure [PVF] were treated by Redo-MVR. Time intervals of reoperations were 5months, 40months, and 35months, respectively. In all cases, valve thromboses were excised successfully. Cineradiography provided an accurate diagnosis in all cases, which was utilized as safe, reliable & noninvasive imaging modalities. There were no operative death & complication. All three patients were fully recovered and returned to their employements, and active lives.

• Journal of Chest Surgery
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• 제41권4호
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• pp.430-438
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• 2008

배경: 기계 심장판막 대치술 후 발생하는 혈전성 합병증을 방지하기 위해 항응고제 치료로써 와파린을 환자에게 투여한다. 이때 환자에 따른 적절한 와파린 용량을 결정하기 위한 지표로서 INR을 참고하는데 통상 대동맥판막은 $2.0{\sim}3.0$, 승모판막은 $2.5{\sim}3.5$가 참고치로서 받아들여지고 있다. 하지만 임상 경험상 대부분의 환자에서 이 수치로 유지하였을때 출혈성 합병증(비출혈, 혈뇨, 자궁출혈, 뇌출혈 등)이 빈번하게 발생하여 참고치보다 더 낮게 유지하는 경우가 많다. 이에 본원에서는 기계 심장판막 환자들을 후향적으로 조사하여 혈전성 합병증의 빈도가 낮은 적정한 INR을 알아보고자 한다. 대상 및 방법: 1984년 1월부터 2007년 2월까지 이엽성 기계 심장판막 대치술을 받고 생존한 311명의 환자를 대상으로 후향적으로 조사하였다. 대동맥판막치환 환자들(60명)은 INR $1.5{\sim}2.0$ (1군), $2.0{\sim}2.5$ (2군), 2.5 (3군) 이상의 세 군으로 나누고 승모판막치환(171명)이나 승모판막과 대동맥판막을 동시에 치환한 환자들(80명)은 INR $1.5{\sim}2.0$ (1군), $2.0{\sim}2.5$ (2군), $2.5{\sim}3.0$ (3군), 3.0 (4군) 이상의 네군으로 나누어 혈전성 합병증 발생률, 중요출혈성합병증 발생률을 조사하여 각각의 생존함수를 비교하였다. 결과: 대동맥 판막치환 환자 중 혈전성 합병증은 2명, 출혈성합병증은 4명이 발생하였고 세군의 혈전성 합병증의 생존함수의 차이는 관찰되지 않았고 출혈성 합병증의 생존곡선에서 1, 2군과 3군의 차이가 관찰되었다. 승모판막치환이나 승모판막과 대동맥판막을 동시에 치환한 환자들 중 혈전성 합병증은 13명, 출혈성 합병증은 15명이 발생하였고 네 군의 혈전성 합병증의 생존함수의 차이는 관찰되지 않았고 출혈성 합병증은 1, 2군과 3, 4군에서 차이를 보였다. 결론: 모든 판막에서 INR이 $1.5{\sim}2.5$ (1군과 2군)로 유지한 환자들이 그 이상으로 유지한 환자들보다 혈전성 합병증에서 차이를 보이지 않았고 출혈성 합병증에서 유의하게 감소하는 양상을 보여 이엽성 기계판막에서 적정한 INR은 $1.5{\sim}2.5$로 유지하는 것이 바람직하다고 판단된다.

• Journal of Digestive Cancer Research
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• 제10권2호
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• pp.92-98
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• 2022

Self-expandable metal stent (SEMS) is effective for biliary drainage, especially in pancreaticobiliary cancer. The mechanical properties, material, and design of SEMS are important in preventing recurrent biliary obstruction and complication. Radial and chronic expansion forces play roles in preventing stent migration and collapse. Complications, such as stent impaction, cholecystitis, and pancreatitis, were related to the axial force. The nickel-titanium alloy shows more flexibility, conformability, and optimal axial force compared to previously used stainless steel. Additionally, the stent structure affected the mechanical properties of SEMS. Therefore, understanding the mechanical properties, material, and design of SEMS will provide the best outcome for biliary drainage, as well as better SEMS development.

• Journal of Chest Surgery
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• 제26권8호
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• pp.620-626
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• 1993

Determination of preoperatibe pulmonary function is crucial in avoiding complications from pulmonary resection, especially pneumonectomy. Postoperative morbidity and mortality were correlated with the preoperative results of five widely used tests of pulmonary function in 40 patients who underwent pneumonectomy for bronchiectasis, pulmonary tuberculosis, and carcinoma of the lung. Factors analyzed following operation included 30-day mortality, the incidence of arrhythmia, the frepuency of respiratory complications, and the number of individuals requiring prolonged mechanical ventilation. There were statistically significant differences[p<0.001]in mean values among FVC, FEV1, FEV1/FVC and MVV. But the difference of the FEF25-75% was not statistically significant.

• The Journal of Advanced Prosthodontics
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• 제14권4호
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• pp.223-235
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• 2022

PURPOSE. To compare the clinical outcomes of two types of implant restoration for posterior edentulous area, 3-unit bridge supported by 2 implants and 3 implant-supported splinted crowns. MATERIALS AND METHODS. The data included 127 implant-supported fixed restorations in 85 patients: 37 restorations of 3-unit bridge supported by 2 implants (2-IB), 37 restorations of 3 implant-supported splinted crowns (3-IC), and 53 single restorations (S) as controls. Peri-implantitis and mechanical complications that occurred for 14 years were analyzed by multivariable Cox regression model. Kaplan-Meier curves and the multivariable Cox regression model were used to analyze the success and survival of implants. RESULTS. Peri-implantitis occurred in 28.4% of 2-IB group, 37.8% of 3-IC group, and 28.3% of S control group with no significant difference. According to the implant position, middle implants (P2) of the 3-IC group had the highest risk of peri-implantitis. The 3-IC group showed a lower mechanical complication rate (7.2%) than the 2-IB (16.2%) and S control group (20.8%). The cumulative success rate was 52.8% in S (control) group, 62.2% in 2-IB group, and 60.4% in 3-IC group. The cumulative survival rate was 98.1% in S (control) group, 98.6% in 2-IB group, and 95.5% in 3-IC group. There was no significant difference in the success and survival rate according to the restoration type. CONCLUSION. The restoration type was not associated with the success and survival of implants. The risk of mechanical complications was reduced in 3 implant-supported splinted crowns. However, the middle implants of the 3 implant-supported splinted crowns had a higher risk of peri-implantitis.

• Journal of Chest Surgery
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• 제25권8호
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• pp.800-805
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• 1992

Acquired, nonmalignant tracheoesophageal fistula is an uncommom and difficult problem to manage. The most commom cause is a complication of endotracheal or tracheostomy tubes. Most are diagnosed while patients still require mechanical ventilation. The principle of treatment is two stage operation. First, new tracheostomy tube is placed so that the baloon is below the fistula, and gastrostomy and feeding jejunostomy are made for the drainage and feeding. Finally after weaning from the mechanical ventilation, tracheal resection and reconstruction are made, and the esophageal defect is closed in two layers and a viable strap muscle interposed into the two suture site to prevent recurrence. Recently, we experienced a case of acquired nonmalignant tracheoesophageal fistula which was developed during mechanical ventilation. She was successfully treated with the above two stage operation.