• The Journal of Advanced Prosthodontics
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• 제14권5호
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• pp.305-314
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• 2022

PURPOSE. The aim of this study was to evaluate the flexural strength of a 3D-printed denture base resin (Cosmos Denture), after different immediate repair techniques with surface treatments and thermocycling. MATERIALS AND METHODS. Rectangular 3D-printed denture base resin (Cosmos Denture) specimens (N = 130) were thermocycled (5,000 cycles, 5℃ and 55℃) before and after the different repair techniques (n = 10 per group) using an autopolymerized acrylic resin (Jet, J) or a hard relining resin (Soft Confort, SC), and different surface treatments: Jet resin monomer for 180 s (MMA), blasting with aluminum oxide (JAT) or erbium: yttrium-aluminum-garnet laser (L). The control group were intact specimens. A three-point flexural strength test was performed, and data (MPa) were analyzed by ANOVA and Games-Howell post hoc test (α = 0.05). Each failure was observed and classified through stereomicroscope images and the surface treatments were viewed by scanning electron microscope (SEM). RESULTS. Control group showed the highest mean of flexural strength, statistically different from the other groups (P < .001), followed by MMA+J group. The groups with L treatment were statistically similar to the MMA groups (P > .05). The JAT+J group was better than the SC and JAT+SC groups (P < .05), but similar to the other groups (P > .05). Adhesive failures were most observed in JAT groups, especially when repaired with SC. The SEM images showed surface changes for all treatments, except JAT alone. CONCLUSION. Denture bases fabricated with 3D-printed resin should be preferably repaired with MMA+J. SC and JAT+SC showed the worst results. Blasting impaired the adhesion of the SC resin.

• 헤리티지:역사와 과학
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• 제53권2호
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• pp.140-155
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• 2020

본 연구는 강진 무위사 극락보전의 수리 자료, 행정 문서 등의 분석을 통해 시기별 벽체 수리 내용을 살펴보고, 건물에 설치된 벽체의 재료와 시공기술이 어떠한 차이점 및 공통점을 갖는지 살펴보는 것을 목적으로 한다. 해체 수리 시기는 1935년, 1956년, 1982~3년 이뤄진 수리를 대상으로 그 전후 시기의 과정을 함께 분석하였으며, 연구를 통해 도출한 결과는 다음과 같다. 첫째, 1935년 해체 수리 시 진행된 벽체공사에서 외엮기는 원래의 것을 준수하고, 초벽·재벌·정벌은 기존과 다른 재료가 사용된 것을 확인하였다. 벽체의 구성 재료에는 초벽은 점토, 석회, 강사, 재벌은 모래, 회반죽, 정벌은 회반죽과 해초풀이 사용되었다. 둘째, 1956년 수리 시 확인한 벽체의 외엮기 구성 방식은 껍질째 가는 잡목을 가로·세로외로 사용하였고, 새끼줄을 이용해 대각선으로 엮는 방법으로 설치된 것을 확인하였다. 또한, 측면 벽체 훼손 상태를 통해 벽선과 유사 크기의 중깃이 상·하인방에 결구된 방식임을 확인하였다. 셋째, 1982~3년 수리공사에서는 외엮기 방식은 재래의 수법을 따른다고 하였고, 직접 피운 생석회(소석회)와 모래, 황토, 여물, 해초풀을 섞어 회사벽을 구성하였다. 넷째, 시기별 수리공사 내용을 종합하였을 때, 외엮기 방식은 1900년 이전의 방식이 명확하였으며, 초벽에 사용된 재료는 1935년 이후 재료의 변화가 있었다. 다섯째, 수리별 사용되는 재료는 달라졌지만, 각 공사마다 유의할 점에 대해 표기한 부분에서 문화재 수리 원칙에 대한 공통적인 견해를 갖고 있는 것으로 볼 수 있다.

• Journal of Chest Surgery
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• 제53권6호
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• pp.346-352
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• 2020

Background: We aimed to assess the clinical outcomes of patients who underwent surgical repair of Kommerell diverticulum (KD) with individualized surgical methods. Methods: A retrospective analysis was performed of adult patients (aged ≥17 years) who underwent surgery to treat KD between June 2008 and October 2019. Results: Nine patients (median age, 45 years; range, 19-67 years; 7 men) underwent surgical repair. The indications for surgical therapy were acute aortic dissection in 2 patients, the presence of compressive symptoms due to dilated KD in 4 patients, and aneurysm growth in 3 patients. Various surgical techniques were used: (1) resection of the diverticulum stump and revascularization of the aberrant subclavian artery (n=3), (2) one-stage total-arch replacement including the diverticulum segment (n=3), and (3) hybrid repair (n=3). Early mortality occurred in 1 case of hybrid repair. Transient paraparesis occurred in a patient who underwent total arch repair as part of complicated acute aortic dissection. During follow-up (median duration, 30 months; range, 7-130 months), no late death or associated aortic complications were documented. All survivors were free from symptoms and had no abnormal findings on follow-up computed tomography. Conclusion: With a customized surgical approach and appropriate consideration of patient-specific anatomy and associated comorbidities, KD can be repaired with favorable outcomes.

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.941-946
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• 2013

Objective: The nucleotide excision repair (NER) and base excision repair (BER) pathways, two DNA repair pathways, are related to platinum resistance in cancer treatment. In this paper, we studied the association between single nucleotide polymorphisms (SNPs) of involved genes and response to platinum-based chemotherapy in epithelial ovarian cancer. Method: Eight SNPs in XRCC1 (BER), XPC and XPD (NER) were assessed in 213 patients with epithelial ovarian cancer using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and primer-introduced restriction analysis-polymerase chain reaction (PIRA-PCR) techniques. Results: The median progression-free survival (PFS) of patients carrying the Lys/Lys and Lys/Gln+Gln/Gln genotype of the XPC Lys/Gln polymorphism were 25 and 12 months, respectively (P=0.039); and the mean overall survival (OS) of patients was 31.1 and 27.8 months, respectively (P=0.048). Cox's multivariate analysis suggested that patients with epithelial ovarian cancer with the Gln allele had an increased risk of death (HR=1.75; 95% CI=1.06-2.91) compared to those with the Lys/Lys genotype. There are no associations between the XPC PAT+/-, XRCC1 Arg194Trp, Arg280His, Arg399Gln, and XPD Asp312Asn, Lys751Gln polymorphisms and the survival of patients with epithelial ovarian cancer when treated with platinum-based chemotherapy. Conclusion: Our results indicated that the XPC Lys939Gln polymorphism may correlate with clinical outcome of patients with epithelial ovarian cancer when treated with platinum-based chemotherapy in Northern China.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제29권3호
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• pp.241-249
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• 2007

An augmentation of the maxillary sinus floor facilitates placement of dental implants in the posterior atrophic maxilla. However, a maxillary sinus augmentation has potential complications that can lead to early failure and loss of the bone graft. One specific complication is sinus membrane perforation. Especially, large perforations may cause loss of the graft materials into the sinus and infection, so, early failure of the sinus lift. Attempts at managing sinus membrane perforations are difficult because of the limited access to them and friability of the thin Schneiderian membrane. Repair of sinus membrane perforations intraoperatively may be performed using a variety of techniques and materials, including sutures, collagen membranes, fibrin glue. Inspite of various repair technique, as has been reported extensively in the literature, large perforations represent an absolute contraindication to the continuation of surgery. But, we obtained clinically favorable results in cases that show repair of the perforated sinus membrane with a micro-suture technique by 4X Loupe ($Surgitel^{(R)}$ Loupe, General Scientific Corporation) in large perforation. The objective of this presentation is to report of several cases of repair of the perforated sinus membrane with micro-suture technique using 7.0 or 8.0 suture materials, to make a brief review of the literature about various technique managing perforated sinus membrane.

• 건축역사연구
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• 제23권1호
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• pp.7-19
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• 2014

This study considers the proper repair techniques by examining the most representative repair cases of the Korean arch bridges and proposes the constructional manual which can apply similar occasions. The cases are Seonamsa Seungseongyo and Songgwangsa Geukrockgyo where this researcher had taken part in the repair works. This Study proposes the maintenance construction manual about the performance degradation drew by performance degradation of the both Korean arch bridges in the maintenance process. First, arch bridge maintenance should be carried out in the dry season, when water is impermeable in the bottom surface of the bridge. Moreover, risk factors of the maintenance should be excluded to secure the water vally flow, the bypass and the temporary bridge. Second, prior to repair, it has to precede (1)3D shooting (2)formal examination (3)structure safety test (4)geological and lithic surveys (5)arch curvature establishment and makeshift frame settlement before transformation (6)relationship expert comments. Third, if the baduk and the foundation stones are inevitable to replace due to performance degradation on the foundation, it should use the high quality stones and secure greater stress by extending the standard range. The foundation on irregular rock needs to be flattened and underside on the replaced materials require Grengyijil to deliver the equal loads. Fourth, In the process of dismantling the stones of the arched bridge, it could make heavy weathering degree and not reuse the materials. Charge should converge the expert advices to choose the reuseable, the conservate and the alternative materials, and increase the reutilization of the raw materials by preservation and reinforcement treatments. Fifth, the side wall should be repaired by the rubble work technique which is not able to pile compost satiety, so it must use long depth of masonary stones for reinforcement. It is considered to reinforce the stone wall in shore as much as possible and protect the abutment and the side wall on the upstream for the arch bridge maintenance works.

• 한국구조물진단유지관리공학회 논문집
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• 제15권1호
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• pp.226-234
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• 2011

해양환경 하에서 염화물의 침투를 억제하여 부식 위험을 최소화함으로써 콘크리트 구조물의 공용기간을 연장할 수 있다. 효과적으로 구조물을 관리하기 위해 적절하게 유지관리하는 것이 필요하다. 본 연구에서는 효과적인 유지관리 전략을 세우기 위한 보수된 구조물의 유지관리비용 평가와 연계하여 구조물의 사용수명을 정량적으로 평가하는 방법을 제안하였다. Fick의 제2법칙으로부터 Crank-Nicolson법에 기초한 유한 차분법을 제안하여 보수되지 않은 콘크리트 구조물과 보수된 콘크리트 구조물의 염화물 이온 분포를 예측하였다. 이를 이용하여 보수에 의해 연장 가능한 사용수명과 목표한 공용기간 동안에 필요한 보수 횟수를 평가하였다. 게다가 보수 횟수와 콘크리트 교체 비용을 고려하여 총 유지관리 비용을 산출하였다. 마지막으로 제안된 방법의 적용성 검토를 위해 수치해석 예제를 제시하였다.

• Clinics in Shoulder and Elbow
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• 제26권3호
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• pp.276-286
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• 2023

Background: The transosseous anchorless repair (ToR) technique was recently introduced to avoid suture anchor-related problems. While favorable outcomes of the ToR technique have been reported, no previous studies on peri-implant cyst formation with the ToR technique exist. Therefore, this study compared the clinical outcomes and prevalence of peri-implant cyst formation between the ToR technique and the conventional transosseous equivalent technique using suture anchors (SA). Methods: Cases with arthroscopic rotator cuff repair (ARCR) between 2016 and 2018 treated with the double-row suture bridge technique were retrospectively reviewed. Patients were divided into ToR and SA groups. To compare clinical outcomes, 19 ToR and 57 SA cases without intraoperative implant failure were selected using propensity score matching (PSM). While intraoperative implant failure rate was analyzed before PSM, retear rate, peri-implant cyst formation rate, and functional outcomes were compared after PSM. Results: The intraoperative implant failure rate (ToR, 8% vs. SA, 15.3%) and retear rate (ToR, 5.3% vs. SA, 19.3%) did not differ between the two groups (all P>0.05). However, peri-implant cysts were not observed in the ToR group, while they were observed in 16.7% of the SA group (P=0.008). Postoperative functional outcomes were not significantly different between the two groups (all P>0.05). Conclusions: The ToR technique produced comparable clinical outcomes to conventional techniques. Considering the prospect of potential additional surgeries, the absence of peri-implant cyst formation might be an advantage of ToR. Furthermore, ToR might reduce the medical costs related to suture anchors and, thereby, could be a useful option for ARCR. Level of evidence: III.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.1185-1192
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• 2001

This paper reviews available techniques for monitoring corrosion of steel in concrete. The need for early detection and diagnosis of corrosion related deterioration in reinforced structures is widely acknowledged. This is particularly important in reinforced concrete structures on account of the economic and social significance of the problem. The current generally used on-site procedure for corrosion monitoring of reinforced structures employs a method of half-cell surface potential measurements. While the technique has provided a useful means of delineating areas of high or low corrosion risk, there are difficulties in its use and interpretation when assessing rates of deterioration. Electrochemical techniques are by far the most suitable for corrosion monitoring purpose and meet most of the requirements. The aim of this paper is to describe the electric resistance sensor(ER sensor) and electrochemical techniques employed to monitor and estimate corrosion rates of reinforcement. Early detection and diagnosis of corrosion hazards allows preventive measures to be taken, hence the typically expensive repair of severely deteriorated structures can be avoided.

• Geomechanics and Engineering
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• 제15권1호
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• pp.631-643
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• 2018

The estimation of the strength and other mechanical parameters characterizing the tensile behavior of granites can play an important role in civil engineering tasks such as design, construction, rehabilitation and repair of existing structures. The purpose of this paper is to apply data mining techniques, such as multiple regression (MR), artificial neural networks (ANN) and support vector machines (SVM) to estimate the mechanical properties of granites. In a first phase, the mechanical parameters defining the complete tensile behavior are estimated based on the tensile strength. In a second phase, the estimation of the mechanical properties is carried out from different combination of the physical properties (ultrasonic pulse velocity, porosity and density). It was observed that the estimation of the mechanical properties can be optimized by combining different physical properties. Besides, it was seen that artificial neural networks and support vector machines performed better than multiple regression model.