• Imaging Science in Dentistry
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• 제43권2호
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• pp.123-128
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• 2013

Double tooth is a dental anomaly consequent to fusion of two or more teeth or gemination of a single tooth. This report describes a unique case of double tooth in relation to a mandibular lateral incisor exhibiting the presence of four root canals. The role of conventional radiography and advanced three-dimensional imaging techniques in the better assessment of complex root canal systems and their aid in endodontic management has also been highlighted.

• 대한치과의사협회지
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• 제21권6호통권169호
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• pp.467-472
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• 1983

Thirty seven human maxillary third mooars were injected with china ink, decalcified, cleared, and used in vitro study to determine the number of root canals the frequency and location of lateral canals, canals per root, and frequency of apical deltas. The results were as follows: 1. Less than half of the examined teeth showed 3 roots and 3 canals. 2. The mesiobuccal root was ound to contain a single primary canal in 65.4% of the teeth examined and two canals in 34.6% of the teeth studed. 3. In mesiobuccal roots with two canals, the separated apical foramen appeared 30.8% of the specimen concerned, but no common apical foramen appeared. 4. Of the 106 canals studied, 46.2% of the canals were found to contain lateral canals and these ramifications were mainly located in the apical third of the root.

• Fisheries and Aquatic Sciences
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• 제10권4호
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• pp.196-199
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• 2007

The spermatozoa of Leiocassis nitidus are relatively simple cells composed of a spherical head, a short midpiece, and a tail, as in most Siluriformes. The ultrastructure is characterized by the following features: Acrosome absent, as in most teleosts; around nucleus about $1.8\;{\mu}m$ long, with a deep nuclear fossa containing the proximal and distal centrioles and mitochondria. Two centrioles approximately $180^{\circ}$ from each other; 10 or more mitochondria surrounding the axoneme (with a 9+2 microtubular pattern), arranged in two layers in the postnuclear cytoplasm and separated from the axoneme by the cytoplasmic canal. Two lateral fins on the same plane as the two central microtubules; doublets 3 and 8, which are ultrastructural characteristics of the sperma tail unlike other siluroids laking the lateral fins.

• 대한임상검사과학회지
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• 제40권1호
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• pp.62-70
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• 2008

Benign paroxysmal positional vertigo (BPPV) is one of the most common clinical entities encountered in a dizzness clinic. Retrosepective review was performed for the patient's diagnosed as BPPV at Sunchon "S" hospital dizzness center. Variables for statistical analysis included age, sex, involved canal presence of recent head tramua, presence of chronic otitis media, history of middle ear surgery, underlying disease such as hypertension or diabetics, headache, central lesion. From July 2004 to May 2005, we sampled the 600 dizzness patient's who visited the dizzness center. Dizzness could be classified into BPPV, vestibulopathy. Among these patients, 256 patients had BPPV, 222 patients had vesibulopathy and 97 patients had Normal. Among these BPPV patients, 80 patients had lateral canalolithiasis BPPV (31.3%), 28 patients had lateral cupulolithiasis BPPV (10.9%), 90 patients had posterior canalolithiasis BPPV (35.2%), 7 patients had multicanalolithiasis BPPV (2.3%), 52 patients simultaneously had BPPV, other vestibular disease, and central lesion (20.3%).

• Restorative Dentistry and Endodontics
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• 제15권1호
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• pp.81-87
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• 1990

The purpose of this study was to evaluate the apical seal produced by low temperature($70^{\circ}C$) injection gutta percha technique(ULTRAFIL) with & without sealer, warm latero-vertical cindensation technique (ENDOTEC) with & without sealer, and the lateral condensation technique with sealer. 100 extracted, single rooted human teeth were divided into 5 groups and root canals were enlarged & obturated according to the purpose of this study. Obturated teeth were immersed in 2.5% methylene blue for 48hrs. at $37^{\circ}C$ incubator and split. The apical sealing ability was evaluated by measuring the degree of dye penetration into the canal. The results were as follows: 1. All group showed varying depth of dye penetration. 2. There were no significant difference among Group I (lateral condensation), Group II (ULTRAFIL with sealer) & Group IV (ENDOTEC with sealer) (P>0.05). 3. There were less dye penetration when used in conjunction with sealer (P<0.001).

• Restorative Dentistry and Endodontics
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• 제37권1호
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• pp.50-53
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• 2012

Cone-beam computed tomography (CBCT) is a useful diagnostic tool for identification of both internal and external root configurations. This case report describes the endodontic management of a lateral incisor with both dens invaginatus and external root irregularity by using CBCT. Nonsurgical endodontic retreatment was performed on the lateral incisor with dens invaginatus. A perforation through the dens invaginatus and external concavity was repaired using mineral trioxide aggregate. After 18 mon of follow-up, there were no clinical symptoms. Recall radiographs appeared normal and showed healing of the periapical pathosis. The understanding of both internal root canal configuration and external root irregularity using CBCT can ensure predictable and successful results.

• Restorative Dentistry and Endodontics
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• 제47권4호
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• pp.40.1-40.18
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• 2022

Objectives: This study aimed to investigate the influence of different obturation techniques compared to cold lateral compaction on the success rate of primary non-surgical endodontic treatments. Materials and Methods: Systematic searches were performed for studies published up to May 17^th, 2022 in MEDLINE/PubMed, Cochrane Library, Web of Science, Scopus, EMBASE, and Grey Literature Reports. Randomized clinical trials and nonrandomized (nonrandomized clinical trials, prospective or retrospective) studies that evaluated the success rate of primary non-surgical endodontic treatments obturated with the cold lateral compaction (control) and other obturation techniques were included. The revised Cochrane risk of bias tools for randomized trials (RoB 2) and nonrandomized studies of interventions (ROBINS-I) were used to evaluate the risk of bias. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool was used to evaluate the certainty of evidence. Results: Eleven studies (4 randomized clinical trials (RCTs), 4 prospective, and 3 retrospectives) were included. Two RCTs were classified as having some concerns risk of bias and 2 as a low risk of bias. Two nonrandomized studies were classified as having a critical risk of bias and 5 as having a moderate risk of bias. The GRADE analysis demonstrated a very low to moderate certainty of evidence. Conclusions: This systematic review generally evidenced no differences in the success rate of primary non-surgical endodontic treatments when the cold lateral compaction technique and other obturation techniques are performed. Further well-designed studies are still necessary.

• 한국어류학회지
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• 제18권4호
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• pp.347-354
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• 2006

참갈겨니(Zacco koreanus) 정세포 변형과정과 성숙한 정자의 미세구조를 주사 및 투과 전자 현미경으로 관찰하였다. 참갈겨니 Z. koreanus 정세포변형과정은 수중형 Type II과 유사하나 기부중심립이 핵와안에 위치해 있는 점에서 일부 차이가 있었다. 또한 두 중심립은 섬유성 물질에 의하여 상호연결되어 있는데 이와 같은 구조는 잉어류에서 공통적으로 나타나고 있다. 편모에서 관찰되는 vesicle은 잉어류의 공통된 형질로 사료되며 Charciformes와 일부 Siluriformes에서도 관찰되고 있어 이들 분류군의 계통적 유연관계를 추정할 수 있는 구조적 특징으로 사료된다.

• 한국어류학회지
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• 제22권3호
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• pp.206-209
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• 2010

망둑어과(Family Gobiidae)에 속하는 Redigobius bikolanus 1개체가 제주도 서귀포시 안덕면 창고천의 기수 지역에서 채집되었다. 이 종은 측선 비늘수 26~28개, 측선상부 비늘수 6~8개, 측선하부 비늘수 7개, 뒷지느러미 기점에서 꼬리지느러미 밑 기점까지 4개의 점이 있으며, 암컷의 경우 위턱의 뒤 가장자리가 눈의 앞부분까지 도달하며, 수컷의 경우 위턱의 뒤 가장자리가 눈을 지나는 특징을 갖고 있다. 본 종의 신한국명을 "점박이망둑"이라고 명명하였다.

• 한국어류학회지
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• 제21권2호
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• pp.81-86
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• 2009

한국산 동자개 Pseudobagrus fulvidraco의 정세포변형과 성숙한 정자의 미세구조를 주사 및 투과전자현미경으로 관찰하였다. 정세포변형은 측면에서 발생되는 편모, 핵의 회전, 염색물질로 채워진 핵의 함입과 핵와의 형성이 특징적이었다. 성숙한 정자의 구조는 첨체가 없는 둥근두부와 짧은중편 그리고 긴 편모로 구성되어 있었다. 짧은 중편에는 다수의 미토콘드리아가 있으며 cytoplasmic canal에 의하여 편모와 분리되어 있었다. 편모는 전형적인 9+2 구조이며 axonemal fins를 가지고 있었다. Axonemal fins는 동자개과에서 공통적으로 나타나는 형질로 여겨지며 그 외 다른 특징을 경골어류에서 비교하였다.