• Restorative Dentistry and Endodontics
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• 제30권6호
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• pp.461-469
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• 2005

한 개의 치근을 가진 상, 하악 소구치의 방사선 사진 상의 근관계와 동일치아의 투명표본 상의 근관계를 각각 관찰한 다음 상호 비교하기 위해 총 142개의 소구치를 선택한 후, 구내 치과용 표준 방사선 필름을 이용하여 근원심과 협설측으로 방사선을 채득하였다. 동일하게 교육받은 4명의 판독자가 방사전 사진을 판독하여 근관계의 형태를 분류하였다. 동일한 치아에 근판와동을 형성한 후 $5\%$ 질산용액에 48시간 동안 담가 치수조직을 용해시키고 인디안 잉크를 치수강 내로 주입하여 치수조직을 염색하였다. $5\%$ 질산용액에 48시간 동안 담가 탈회시킨 후 메틸 살리실레이트로 투명화시키고 입체현미경하에서 20배의 크기로 근관계의 형태를 평가하여 다음과 같은 결과를 얻었다. 방사선과 입체현미경 소견간에는 판독자 간에 통계학적으로 유의한 차이를 나타냈다 (p<0.05). 따라서 동일한 방사선 사진을 판독할 경우 판독자 간에 근관의 형태에 있어서 차이가 있을 수 있다. 그러므로 임상가는 방사전 사진을 주의깊은 판독과 예견된 근관의 형태에 따라 난이도를 고려하여 근관치료를 시행해야 할 것으로 사료된다.

• 경영과정보연구
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• 제31권3호
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• pp.117-139
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• 2012

본 연구의 목적은 회계투명성과 기업의 사회적 책임이 재무성과 및 기업가치와의 관련성을 살펴보는 것이다. 그러나 우리나라에서는 사회적 책임에 관한 지표가 보편타당한 것이 아니라 특정 연구소에서 조사하고 있는 지표를 주로 사용하고 있기 때문에 보다 신뢰성 있는 연구를 위해, 먼저 선행연구에서 연구된 결과들을 바탕으로 기업의 투명성 변수를 살펴본 뒤 그 연구를 기반으로 사회적 책임과 재무성과 및 기업가치와의 관련성을 살펴보고자 한다. 본 연구의 분석결과를 요약하면 다음과 같다. 첫째, 종속변수가 ROA인 경우 자산의 질(QAS) 변수만 제외하고 모두 유의적인 관련성을 나타내었고, 종속변수를 Tobin's Q로 한 분석에서는 매출액순이익률(CITSA), 매출채권비율(SCTSA), 판매관리비비율(SETR) 그리고 매출액성장율(SATSA)이 유의적인 관련성을 보였다. 따라서 가설 1은 모든 변수는 아니지만 부분적으로는 받아들여졌다. 둘째, 가설 2와 3의 검증을 위해 투명성 변수에 따라 모형을 4가지로 나누어 분석한 결과, '전체-ROA'와 'ROA'모형 그리고 '전체-Tobin's Q'와 'Tobin's Q' 모형에서도 lnCSR과 TranD${\times}$lnCSR이 유의적인 양(+)의 관계를 나타내어 가설 2와 가설 3이 받아들여졌다. 본 연구의 차별점은 지금까지 거의 연구가 이루어지지 않았던 기업의 사회적 책임과 회계투명성을 연결시켜 기업의 사회적 책임과 투명성 그리고 기업가치와 관련성을 분석하였다는 점과, 발표되지 않는 자료를 포함하여(약 360개 기업) 표본을 확장하여 연구를 일반화하였다는 점을 들 수 있다.

• 대한치과의사협회지
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• 제15권11호
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• pp.753-756
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• 1977

Eighty-two maxillary canine were injected with china ink, decalcified, cleared and used in a study, in vitro, to determine the number of root canals, the frequency and location of lateral canals, the location of apical foramens, and the curvature of root canals. The results were as follows; 1.All of the maxillary canines showed the single canals. 2. Of the 82 canals studied, 20.7% of the canals were found to have lateral canals and most ramification of them were located in the apical third of the root. 3. In the case of the curvature, the mesial curvature of the canals (40.3%) usually showed more than the distal curvature of them (13.4%) 4. 41.2% of the apical foramen were located directly on the root apex and 58.5% of them laterally.

• 대한치과의사협회지
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• 제16권12호통권115호
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• pp.929-933
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• 1978

Sixty six mandibular incisor were injected with China ink, decalcified, cleared and used to study the number of root canals, the frequency and location of lateral canals, the location of apical foramens, the frequency of apical deltas, and the curvature of root canals. The results were as follows: 1. Most of the teeth demonstrated single canal, but 19.7% of the teeth were found to have bifurcated canals. 2. 12% of the teeth were found to have lateral canals and these ramifications were located in the apical third of the root. 3. 25 apical foramens were located directly on the root apex and 41 foramens laterally. 4. 43 canals showed straight, 7 canals distal curvature, 7 labial curvature, 3 mesial curvature.

• Restorative Dentistry and Endodontics
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• 제9권1호
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• pp.121-125
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• 1983

Thirty eight mandibular second premolars were injected with china ink, decalcified, cleared and used in an in vitro study to determine the number of root canals, the frequency and location of lateral canals, the location of apical foramens, the frequency of apical deltas, and the curvature of root canals. The results were as follows: 1. Most of the teeth demonstrated single canal, but 5.3% of the teeth were found to have bifurcated or trifurcated canals. 2. Of the 40 canals studied, 52.5% of the canals were found to have lateral canals and these ramifications were usually located in the apical third of the root. 3. 7 apical foramens were located directly on the root apex and 31 foramens laterally. 4. 4 canals showed mesial curvature, 20 canals distal curvature, 11 canals buccal curvature, and 8 canals lingual curvature.

• 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.

• Restorative Dentistry and Endodontics
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• 제15권2호
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• pp.115-121
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• 1990

Forty extracted human mandibular second molars with C-shaped canal were chosen to study the anatomy of the root canal. The experimental teeth were injected with china ink, decalcified and cleared with Winter green oil, in vitro, to study the number of root, root canal, canal per root, frequency and location of lateral canal and transverse anastomosis. 1. All teedth had one root. 2. Mesial roots with two canals were 25%, and mesial roots with one canal were 75%. All distal roots had one canal. 3. In the roots with two canals, the common apical foramen appeared in 20% and the separte apical foramen appeared in 80%. 4. The frequence of lateral canal was 33.3% and the most frequent region was middle 1/3. 5. All teeth had the transverse anastomosis in all region of the roots.

• Restorative Dentistry and Endodontics
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• 제2권1호
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• pp.27-31
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• 1976

Eighty mandibular first premolars were injected with china ink, decalcified, cleared and used in an in vitro study to determine the number of root canals, the frequency and location of lateral canals, the location of apical foramens, the frequency of apical deltas, and the curvature of root canals. The results were as follows: 1. Most of the teeth demonstrated single canal, but 22.5% of the teeth were found to have bifurcated or trifurcated canals. 2. Of the 99 canals studied, 37.3% of the canals were found to have lateral canals and these ramifications were usually located in the apical third of the root. 3. 27 apical foramens were located directly on the root apex and 66 foramens laterally. 4. 6 canals showed mesial curvature, 49 canals distal curvature, 11 canals buccal curvature, and 25 canals lingual curvature.

• Restorative Dentistry and Endodontics
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• 제8권1호
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• pp.139-145
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• 1982

Eighty four human maxillary second premolars were injected with china. ink, decalcified, cleared and used in study, in vitro, to determine the number of root canals, the frequency and location of lateral canals, the frequency and location of transverse ansatomoses, the curvature of root canals, the location of apical foramens, and the frequency of apical deltas. The results were as follows: 1. Most of the teeth demonstrated one canals, but the only tooth was found to have two canal. 2. Of the 101 canals studied, 85.1% of the canals were found to have lateral canals and these ramifications were usually located in the apical third of the root. 3. Of the two root canals in one root, 25.4% of the canals were found to have transverse anastomoses and were usually located in the middle third of the root 4. 33.3% of apical foramens were located directly on the root apex and 66.7% of them laterally, and 46.5% of canals showed distal curvature.

• Restorative Dentistry and Endodontics
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• 제10권1호
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• pp.183-186
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• 1984

Thirty maxillary lateral incisors were injected with china ink, decalcified, cleared and used in an in vitro study to determine the number of root canals, the frequency and location of lateral canals, the location of apical foramens, the frequency of apical deltas, and the curvature of root canals. The results were as follows: 1. Most of the teeth demonstrated single canal, but 6.7% of the teeth were found to have bifurcated canals. 2. Of the 32 canals studied, 37.5% of the canals were found to have lateral canals and these ramifications were usually located in the and apical third of the root. 3. 9 apical foramens were located directly on the root apex and 21 foramens laterally. 4. 3 canals showed mesial curvature, 20 canals distal curvature, 4 canals labial curvature, and 3 canals palatal curvature.