• Restorative Dentistry and Endodontics
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• 제23권2호
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• pp.682-689
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• 1998

The purpose of this study was to evaluate the sealing ability of the Microseal$^{(R)}$, which was new obturation system made by Tycom company, U.S.A. Forty-five extracted single-rooted human teeth were resected at cemento-enamel junction and divided three groups. All canals were prepared using Profile system, and then each group was obturated by lateral condensation technique (group 1), vertical condensation technique (group 2) and Microseal$^{(R)}$ condensation technique (group 3) with root canal sealer. Teeth were immersed in resorcinol-formaldehyde resin for 5 days at $4^{\circ}C$ and the resin was allowed to polymerize completely for 4 days at room temperature. Teeth were resected horizontally at 1 mm (level I), 2 mm (level II), 3 mm (level III) from the anatomical root apex using low speed microtome and examined with Image analyzer (IBASR, Zeiss co., Germany.) at ${\times}25$ magnification. The gab between the canal wall and the filling material, which was filled with the resin, was measured at each of the three levels. Each ratio of leakage was expressed percentage by calculating the ratio of the area of the resin to the total area of the canal and was analyzed statistically (one-way ANOVA). The results were as follows; 1. The mean ratio of leakage (%) was 6.46% at group 1, 3.06% at group 2, 11.27% at group 3. 2. When evaluating the ratio of leakage at the three levels, there was level I> level II> level III in all groups. Especially, the difference between level I and level III was statistically significant (p<0.05). 3. When evaluating the ratio of leakage at the three groups, there was group 3> group 1> group 2 at all levels. Especially the difference between group 2 and group 3 was statistically significant (p<0.05).

• Restorative Dentistry and Endodontics
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• 제24권3호
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• pp.482-489
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• 1999

The purpose of this study was to compare sealing ability between lateral condensation and continuous wave of condensation in depend of root canal curvature. In this study, we divided fifty-six human molar teeth into two group in depend of Schneider method, and then subdivided them into four experimental group (each group is composed of twelve teeth) by canal curvature and obturation method, and eight teeth were served as positive and negative controls. Specimens were prepared by Quantac 2000 series file and obturated by lateral condensation or System B. Specimens were immersed in india ink for 7 days, decalcified by 10% nitric acid, dehydrated by 75, 95 and 100% alcohol in order, cleared by methyl salicylate and then measured of dye penetration with stereomicroscope(${\times}6.5$ magnification) and Image Pro plus. The data were analyzed stastically by one-way ANOVA and Scheffe test. The data were as follows: 1. The mean leakage was $0.725{\pm}1.167$ for group A, $0.813{\pm}0.921$ for group B, $0.809{\pm}0.997$ for group C, $1.111{\pm}1.147$ for group D, but no significant difference among them(p>0.05). 2. Lateral condensation had better sealing ability than continuous wave of condensation, but no significant difference among them(p>0.05). 3. There was no significant difference between root canal curvature degree and microleakage(p>0.05).

• 대한장애인치과학회지
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• 제12권2호
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• pp.72-76
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• 2016

저자는 뇌병변 장애와 보행장애로 반복적인 외상성 치아손상을 받은 환아의 치료를 시행하였다. 최근 실활된 미성숙 영구치의 계속된 치근 형성을 위해 재생적 근관치료 술식이 많이 시도되어 성공적인 결과를 보이고 있다. 하지만 장애로 인해 반복적인 외상의 위험을 가진 환아에서 치수조직의 재생 보다는 치근단형성술을 통한 치근단의 폐쇄와 근관 충전이 비용과 장기적인 예후의 측면에서 유리한 치료방법이 될 수 있음을 확인하였다.

• Restorative Dentistry and Endodontics
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• 제21권2호
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• pp.628-634
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• 1996

The purpose of this study was to investigate the effect of moisture on apical sealing properties of root canal. Fifty five single rooted human teeth were selected from maxillary and mandibular teeth. After removing crown portion at the cemento-enamel junction, all teeth were routinely prepared with step-back method. And then, the canals were dried with paper point and the teeth were randomly divided into 3 groups of 15 teeth each, and remaining 10 teeth were used as positive and negative control teeth : Group 1 were irrigated with 1ml of 95% alcohol and dried with air and paper point. Group 2 and 3 were intentionally contaminated with 0.05ml of 3.5% NaOCl or saliva, respectively. All the teeth were obturated with sealapex and gutta percha cone by lateral condensation technique, and covered with two coat of nail varnish after 48 hours of obturation. The teeth were immersed in india ink for 1 week and cleaned with methyl salicylate and then the degree of dye penetration were measured with stereomicroscope. The data were analyzed statistically by one-way ANOVA. The results were as follows : 1. All experimental groups showed varying degrees of dye penetration, and the mean degree of dye penetration was 0.1mm to 0.7mm. 2. Saliva contamination group(group 3) showed the highest amount of dye penetration, followed by NaOCl contamination group, then alcohol dried group, but there was no significant difference among three experimental groups. * This results suggest that there was no significant differences of apical leakage after canal obturation between alcohol dried canal and moisture present canals and the use of alcohol instead of paper point is unnecessary to dry the canals prior to canal filling. But other factors such as bacterial contamination and sealer discoloration by moisture must be considered in application of this results to clinical practice.

• Restorative Dentistry and Endodontics
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• 제34권2호
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• pp.103-112
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• 2009

본 연구에서는 2종의 이원중합 레진시멘트 (RelyX ARC와 Variolink II)를 이용하여 접착제와 레진시멘트의 중합방법 (자가중합과 광중합)이 섬유포스트와 근관 상아질의 결합강도와 접착계면에 미치는 영향을 상호 비교하기 위하여 시행하였다. 단근관을 갖는 발거된 32개의 하악 소구치에 근관을 충전한 후, FRC Postec system의 Reamer로 9 mm 깊이의 포스트 공간을 형성하였다. 레진시멘트의 종류와 중합방법에 따라 4개의 군 (R-SC군, R-LC군, V-SC군, V-LC군)으로 분류하였다. 포스트 공간에 각 군의 접착제를 도포한 후 레진시멘트를 주입하고, No. 3 FRC Postec 포스트를 위치시켜 자가중합 또는 광중합시켰다. 각 군의 치근을 실온의 증류수에 24시간동안 보관한 다음, 저속의 diamond wheel saw를 이용하여 치관부에서 치근단부를 향해 1.5 mm두께로 연속적으로 횡절단하여 1개의 치근에서 3개의 절편을 얻었다. 각 군의 절편 (31개)은 만능시험기에서 push-out 검사를 시행하였고, 각 군의 강도 값은 반복측정 two-way ANOVA와 one-way ANOVA를 이용하여 비교 분석하였다. 각 군의 절편 (3개)은 주사전자현미경하에서 섬유포스트, 레진시멘트 및 치근 상아질 간의 계면을 관찰, 비교하였다. 본 연구의 결과 전 부식 레진시멘트를 이용하여 섬유포스트를 포스트 공간에 합착할 경우, 접착제와 레진시멘트의 중합방법은 근관 상아질의 결합강도에 영향을 주었으며, 광중합보다 자가중합 방법 이 우수한 결합강도와 계면을 나타내었다.

• Restorative Dentistry and Endodontics
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• 제35권6호
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• pp.445-452
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• 2010

연구목적: 이 연구의 목적은 새로운 근단 역충전 재료를 개발하기 위해 MTA, MTA와 AH-plus 혼합물 (AMTA), 그리고 실험적 개발재료인 Portland cement-Epoxy resin composite (EPPC)의 미세 누출 및 물리적인 성질을 비교하는 것이다. 연구 재료 및 방법: 발거 치아 49개를 근관 성형하고 gutta-percha와 sealer로 충전하였다. 각 치아의 치근을 근단부 3 mm에서 절단하고 3 mm 깊이의 역충전 와동을 형성하였다. 15개씩 무작위로 분류한 치근을 세 군으로 나누어 각각 MTA, AMTA, EPPC로 충전하였고 네 개의 치근은 대조군으로 사용하였다. 각 군의 재료로 역충전이 완료된 모든 실험군을 젖은거즈로 덮고 24시간 동안 경화시켰다. 경화 후 72시간 동안 1% methylene blue 염색액에 담근 후, 치근단을 수직 절단하여 사진을 촬영하고 미세 누출을 평가하였다. Vicat apparatus를 사용하여 실험군 별로 경화시간을 측정하였으며, aluminum step wedge를 사용한 디지털 방사선 사진을 촬영하여 각 군의 방사선 불투과도를 평가하였다. 미세누출과 경화시간에 대해 각 군간의 차이를 일원배치분산분석 및 Scheffe 사후 검증으로 유의수준 95%에서 평가하였다. 결과: AMTA와 EPPC는 MTA군에 비해 적은 미세누출량을 보였다 (p < 0.05). AMTA는 가장 높은 방사선 불투과도를 보였으며 개발 재료인 EPPC군은 5 mm aluminum 두께의 방사선 불투과도를 보였다. MTA가 가장 긴 경화시간을 나타낸반면 EPPC군은 다른 군에 비해 초기경화와 최종경화 모두 가장 짧은 경화시간을 나타냈다 (p < 0.05). 결론: 이 연구 조건하에서, 신개발 재료인 EPPC는 치근단 역충전 재료로서 기존의 MTA보다 양호한 밀폐능력과 방사선 불투과성 및 짧은 경화시간 등의 역충전 재료로서 적절한 물리적 성질을 가진 것으로 보인다.

• 대한치과의사협회지
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• 제20권12호통권163호
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• pp.1011-1013
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• 1982

년령이 증가함에 다라 치아도 신체 다른부위와 같이 노화현상이 나타나는데, 특히 보존영역에서는 상아질 및 치수의 노화에 대한 지식은 매우 중요하다고 생각된다. 일반적으로 상아질 및 치수의 노화는 치수강이나 치근관내 석회화된 조직의 양이 증가하고 세포나 혈관의 수가 감소되는 현상으로 나타나며, 임상에서는 흔히 치수강이나 치근관내 pub stone이나 dystrophic calcification을 발견하게 된다. 이러한 노화현상은 년령이 증가한다는 요소외도 우식, 마모, 교모, 또는 치과시술등이 그 원인이 된다고 알려져 있으며 실제 젊은환자에서도 상아질 및 치수가 노화되어 있는 치아를 볼 수 있다. 그러나 대개 년령적으로는 50세에서 60세사이의 환자에서는 치아의 노화가 있을수있는 가능성이 많다고 알려져 있으므로 임상에서 이점을 고려해야될 것으로 생각되며, 또 한가지는 상아질 및 치수에 이와같은 치유의 능력이 저하된다는 사실이다. 이러한 사실은 우리가 광범위한 충전물을 가진 치아에서 치수복조술을 시행할때는 충전물이 없고 우식이 생긴 치아에서 시술여부를 결정할 때 매우 중요한 점이 되고있는것 처럼 보존시술시 고려되어야 할 중요한 점으로 생각된다. 노인에서 보존치료의 결과는 환자가 신장질환이나 위장병, 폐결핵, 당뇨병등 만성적인 전신 질환을 가지고 있는 경우에는 그 치유가 지연되는 경우가 있기는 하나 시술시에 이러한 사실과 년령증가에 따른 치수 및 상아질의 형태학적 변화나 생리적변화등을 고려해서 치료술식을 약간 달리하면 젊은 환자에서와 똑같은 결과를 가져 올수 있다는 확신 또는 중요하다고 보겠다. 본 난에서는 노인환자의 보존치료시에 임상에서 고려해야할 사항들을 충전시술시와 근관치료시로 나누어서 각 시술 별로 간단히 살펴보조져 한다.

• Restorative Dentistry and Endodontics
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• 제24권3호
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• pp.490-494
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• 1999

The aim of this in vitro study was to investigate the coronal leakage of obligate anaerobes into root canals obturated with two different techniques. 48 extracted human teeth with straight, single root canals were prepared with crown-down technique with Profile under copious irrigation until the master apical file was size 40. The teeth were divided randomly into experimental groups (40 teeth) and control groups (8 teeth). In the experimental groups, 20 teeth were obturated with lateral condensation and other 20 teeth were obturated with continuous wave technique with System B. Coronal leakage of two root canal filing technique was evaluated using anaerobic bacterial leakage model with Fusobacterium nucleatum(ATCC 25586) for 60 days. The results were as follows 1. The incidence of bacterial leakage of experimental groups was 65% in group 1 (lateral condensation) and 60% in group 2 (continuous wave technique with System B). This difference was not statistically significant (P>0.05). 2. There was no statistically significant difference(P>0.05) in leakage score between group 1 (lateral condensation) and group2 (continuous wave technique with System B).

• Restorative Dentistry and Endodontics
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• 제17권2호
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• pp.263-286
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• 1992

This study was performed to evaluate and compare the cytotoxic effects of five root canal sealers to several different cell lines. Five root canal sealers were AH-26, N2, Sealapex, Tubliseal, and Vitapex. Each sealers were mixed according to the manufacturer's instructions, and culture media were added to each sealers immediately after mixing (the immediate group) and after three days (the third day group) and seven days (the seventh day group) respectively. And every sealer solutions were diluted to 1:1, 1:2, 1:3 and 1:4. Three different permanent cell lines (HEp-2, McCoy, MRC-S) and human gingival fibroblasts and mononuclear cells were challenged by each sealer solution and the cytopathic effects were evaluated using MTT-ELISA, MTT-microscopy, and lactate dehydrogenase (LD) activity. The results were as follows: 1. In HEp-2 and MRC-5 cells, Vitapex was the least cytotoxic sealers. 2. AH-26 showed mild cytotoxic effects to HEp-2, gingival fibroblast and mononuclear cells. 3. N2 was the most toxic sealer to gingival fibroblast and it showed relatively strong cytotoxicity to HEp-2, McCoy and MRC-S cells. 4. Tubliseal showed strong cytotoxic effects to HEp-2, McCoy, MRC-S, and mononuclear cells. 5. Sealapex showed strong cytotoxic effect to HEp-2, McCoy, and gingival fibroblasts.

• Restorative Dentistry and Endodontics
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• 제16권1호
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• pp.25-40
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• 1991

Four root canal sealers, Apatite Root Sealer I and II composed mainly of hydroxyapatite/tricalciumphosphate, Sealapex containing calcium hydroxide, and Roth Sealer composed of zinc oxide - eugenol were compared on the culture of L929 fibroblasts. MIT (Methyl Thiazole Tetrazolium Bromide) colorimetric technique was used to measure the mitochondrial dehydrogenase activity. Results were as follows: 1. Hydroxyapatite/tricalcium phosphate mixed sealers were significantly less toxic compared with calcium hydroxide and zinc oxide - eugenol type sealers. High pH of the calcium hydroxide sealer and release of eugenol component from the zinc oxide - eugenol type sealer were presumed to be the cause of the toxicity of these two sealers. In no cases, there were more cytoblastic effects in hydroxyapatite/tricalcium phosphate mixed sealers compared to the control groups. 2. In all experimental groups, toxicity was decreased as dilutions were increased. However in zinc oxide-eugenol type sealer the cell activity was weakened for all dilution groups. 3. Regarding the effect of setting time, Apatite I and Sealapex were less toxic as the setting progressed. Apatite II kept constant regardless of the different time ellapsed after setting but Roth sealer revealed significantly higher toxicity for all experimental groups. 4. Comparing two different culture periods of 24 hours and 72 hours, Apatite I showed higher cell activities in longer period(72 hours) while Apatite II did not. Sealapex and Roth sealer, however, showed significantly lower cell activities in longer period.