• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
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• pp.556-556
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• 2003

It is generally agreed that endodontic success often depends on canal debridement, disinfection and canal obturation. Access opening to a canal is one of the key to canal debridement. Advantages of straight line access opening are allowed a greater proportion of the root canal walls to be prepared than conventional lingual access cavities, minimized the loss of the tooth structure, reduced incidence of file fracture in curved canals. The purpose of this study is determine the influence of different access opening methods on fracture strength in endodontically treated teeth.(omitted)

• Restorative Dentistry and Endodontics
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• 제45권3호
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• pp.33.1-33.10
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• 2020

Objectives: This study was conducted to evaluate the effects of traditional and contracted endodontic cavity (TEC and CEC) preparation with the use of Reciproc Blue (RPC B) and One Curve (OC) single-file systems on the amount of apical debris extrusion in mandibular first molar root canals. Materials and Methods: Eighty extracted mandibular first molar teeth were randomly assigned to 4 groups (n = 20) according to the endodontic access cavity shape and the single file system used for root canal preparation (reciprocating motion with the RCP B and rotary motion with the OC): TEC-RPC B, TEC-OC, CEC-RPC B, and CEC-OC. The apically extruded debris during preparation was collected in Eppendorf tubes. The amount of extruded debris was quantified by subtracting the weight of the empty tubes from the weight of the Eppendorf tubes containing the debris. Data were analyzed using 1-way analysis of variance with the Tukey post hoc test. The level of significance was set at p < 0.05. Results: The CEC-RPC B group showed more apical debris extrusion than the TEC-OC and CEC-OC groups (p < 0.05). There were no statistically significant differences in the amount of apical debris extrusion among the TEC-OC, CEC-OC, and TEC-RPC B groups. Conclusions: RPC B caused more apical debris extrusion in the CEC groups than did the OC single-file system. Therefore, it is suggested that the RPC B file should be used carefully in teeth with a CEC.

• 대한치과의사협회지
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• 제48권8호
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• pp.587-593
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• 2010

The management of malignant tumors of the oral cavity requires that the resection should be performed with adequate negative margins. To this end, the surgeon is sometimes required to increase the access to the oral cavity to resect with clear margins although most of our resections can be carried via the transoral route. This article highlights some of the most common surgical accesses to the oral cavity: Peroral approach, mandibulotomy and mandibular swing approach, visor flap approach, upper & lower cheek flap approach, pull-through technique. Also, various modes of management are grossly described according to primary site, size, and stage of the tumors.

• Restorative Dentistry and Endodontics
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• 제46권3호
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• pp.42.1-42.15
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• 2021

Objectives: This study aimed to analyze the main features of the 25 most-cited articles in minimally invasive access cavities. Materials and Methods: An electronic search was conducted on the Clarivate Analytics' Web of Science 'All Databases' to identify the most-cited articles related to this topic. Citation counts were cross-matched with data from Elsevier's Scopus and Google Scholar. Information about authors, contributing institutions and countries, year and journal of publication, study design and topic, access cavity, and keywords were analyzed. Results: The top 25 most-cited articles received a total of 572 (Web of Science), 1,160 (Google Scholar) and 631 (Scopus) citations. It was observed a positive significant association between the number of citations and age of publication (r = 0.6907, p < 0.0001); however, there was no significant association regarding citation density and age of publication (r = -0.2631, p = 0.2038). The Journal of Endodontics made the highest contribution (n = 15, 60%). The United States had the largest number of publications (n = 7) followed by Brazil (n = 4), with the most contributions from the University of Tennessee and Grande Rio University (n = 3), respectively. The highest number of most-cited articles were ex vivo studies (n = 16), and 'fracture resistance' was the major topic studied (n = 10). Conclusions: This study revealed a growing interest for researchers in the field of minimally invasive access cavities. Future trends are focused on the expansion of collaborative networks and the conduction of laboratory studies on under-investigated parameters.

• Journal of Radiation Protection and Research
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• 제10권1호
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• pp.41-49
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• 1985

1,300 MWe 가압경수로 공동내에서 중성자의 흐름해석이 수행되었다. 중성자의 흐름을 해석하는데는 1차원 수송코드인 ANISN, 2차원 수송코드인 DOT3.5, 3차원 Monte Carlo 코드인 TRIPOLI-02와 이들을 접속시켜주는 DOTTRI 등의 전산코드가 이용되었고, 본 계산에 사용된 전산기는 IBM 3033형이었다. 계산된 선속 및 선량율은 900 MW 가압경수로의 공동내에서 측정한 측정치와 비교검토 되었고, 그 결과 중성자 군별로 약간의 오차는 있었으나 전체적으로 큰 오차는 없었다. 이 결과는 대용량의 원자로 차폐설계, 원자로보수시, 기타 원자로 공동내에 출입할 경우에 방사선방어상 필요한 방어수단을 제공하는데 기여하였다.

• Restorative Dentistry and Endodontics
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• 제12권2호
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• pp.17-23
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• 1987

The purpose of this study was to evaluate the sealing properties of endodontic cavity filling materials according to the time intervals after filling. Access cavities were prepared in extracted human premolar or molar teeth and filled with caviton, zinc oxide eugenol cement, zinc oxide eugenol cement with a base of gutta percha stopping and gutta percha stopping. After filling at the intervals of immediate, 2 days and 2 weeks the teeth were immersed for 2 weeks in 1% methylene blue solutions. Longitudinal sections were obtained from approximately center of teeth and the depth of dye penetration into the access cavities were observed by 10${\times}$macrolens. The following results were obtained. I. All the materials experimented showed varying depth of dye penetration. 2. Of the material tested, caviton showed the best marginal sealing qualities regardless of the time intervals after filling and the sealing properties of the gutta percha stopping was the worst. 3. Both in zinc oxide eugenol cement and zinc oxide eugenol cement with a base of gutta percha stopping, the fillings allowed to mature for 2 days in normal saline solution showed the best sealing properties and those with no maturing time revealed the worst sealing qualities. 4. The sealing qualities of zinc oxide eugenol cement with a base of gutta percha stopping revealed slightly lower depth of dye penetration than that of zinc oxide eugenol cements.

• 대한치과의사협회지
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• 제48권4호
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• pp.288-296
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• 2010

Although non-surgical endodontic procedures have high success rates, failures do occur, These can be managed by root canal re-treatment or surgical intervention. Intentional replantation is an accepted endodontic treatment procedure in which a tooth is extracted and treated outside the oral cavity and then inserted into its socket to correct an obvious radiographic or clinical endodontic failure. Intentional replantation is indicated when other endodontic treatments performed to maintain the tooth have failed, or when endodontic periradicular surgery is not feasible. Intentional replantation may be particularly useful in these cases because these difficult to access areas can be maximally treated while the tooth is out of the mouth without damaging the periodontal attachment in adjacent teeth. In conclusion, intentional replantation is a reliable and even predictable procedure, and should be considered more often as a treatment modality in our efforts to maintain the natural dentition.

• 한국광학회:학술대회논문집
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• 한국광학회 2006년도 하계학술발표회 논문집
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• pp.313-314
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• 2006

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2008년도 공동학술대회
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• pp.191-194
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• 2008

터널 시공당시 발생하는 여굴이나 라이닝과 원지반 사이에 발생하는 배면공동은 터널의 안정성에 심각한 문제를 야기할 가능성이 있으므로 모르타르 등으로 반드시 뒷채움 시공을 하여야 한다. 이러한 뒷채움 시공이 필요한 공동의 위치, 규모의 확인 및 뒷채움 시공의 결과를 효과적으로 확인하는 비파괴 방법으로 GPR탐사가 보편적으로 이용되어진다. 본 논문에서는 서울의 ○○ 터널의 천단부에 대하여 뒷채움 시공전 450MHz 주파수 대역의 안테나를 이용하여 연속적인 GPR탐사를 수행하였고, 그 결과 전체 터널구간 중 크고 작은 8개구간의 배면 공동이 존재하고 있음을 확인하였다. 뒷채움 시공 이후에도 동일한 측선에서 GPR탐사를 수행한 결과 시공전에 발견된 배면공동이 모두 효과적으로 메워진 것을 확인할 수 있었으며, 기타 철근이 배근되어진 구간역시 밀착도가 더욱 향상된 것을 확인할 수 있었다.

• Journal of Gastric Cancer
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• 제11권4호
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• pp.230-233
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• 2011

Regarding the removal of a gastric bezoar, laparoscopic surgery was performed and it was shown that the laparoscopic approach is safe and feasible. However, the laparoscopic method has the risk of intraabdominal contamination, when the gastric bezoar is retrieved from the gastric lumen in the peritoneal cavity. We developed and applied a new procedure for the removal of the gastric bezoar using one surgical glove and two wound retractors as a fashion of intragastric single port surgery. Herein we present this new minimal invasive procedure, so named "hybrid access surgery" which involves the use of existing devices and overcomes the weakness of laparoscopic removal of the gastric bezoar. Our new procedure, combining the concept of intragastric and single port access, is acceptable and feasible to retrieve the gastric bezoar. In the future, this procedure may be one of the alternative procedures for retrieving gastric bezoar even when it is incarcerated in the pylorus.