• Restorative Dentistry and Endodontics
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• v.26 no.6
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• pp.499-506
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• 2001

불완전하게 충전되거나 충전이 되지않은 isthmus는 다근치에 있어서 근관치료의 높은 실패율을 나타낸다 따라서 본 연구의 목적은 isthmus를 갖는 근관을 골라 근관계의 기구조작을 시행하고 여러 가지 근관충전 방법을 이용하여 근관을 충전한 다음 근단부 형성시 적절한 파일의 크기와 치근단부의 밀폐효과를 각 부위별로 비교평가 해보고자 하는 것이다. Isthmus를 갖는 66개의 발거한 치아를 대상으로 기구조작을 통하여 근관확대를 완성하고 무작위로 각각 20개씩 3군으로 분류한 다음 아래와 같은 방법으로 근관을 충전하였다. : A군 측방가압충전법으로 충전한 군, B군 Continuous wave 충전법으로 충전한 군, C군 MicroSeal$^{TM}$을 이용하여 충전한 군. 나머지 6개의 치아는 3개씩 양성대조군과 음성대조군으로 정하였으며 기구조작 후 근관은 충전하지 않은 채로 두었다. 대조군을 제외한 모든 군은 각각 제조회사의 지시에 따라 근관충전한 후 각 시편의 치근단부 2mm를 제외하고 나머지 부위는 두겹의 nail polish를 발라주었으며 2% methylene blue용액에 침잠시켰다 일주일 후 꺼내어 흐르는 물에 깨끗이 세척한 다음 치근단 부위에서부터 1mm씩 잘라가면서 20배의 배율에서 염색액의 침투정도를 평가하였다. 염색액의 침투정도는 다음과 같이 평가되었다. A군과 B군에서는 많은 수의 시편에서 4mm 이상의 절단면에 염색액의 침투를 보인 반면 C군에서는 단지 3mm절단면에서 총 20개 중 3개의 시편에서 염색액의 침투를 보였을 뿐 그 이상의 절단면에서는 염색액의 침투를 보이지 않았다. 뿐만 아니라 isthmus를 갖는 제2형 근관계의 근단부 형성은 40번 크기보다는 큰 MAF가 요구되는 것으로 나타났다. 이러한 결과를 비추어볼 때 isthmus를 갖는 다근치에서 근관충전시 적어도 40번 이상의 MAF로 근단부 형성을 한 후, 열가소성 Continuous wave 충전법과 MicroSeal$^{TM}$을 이용한 근관충전법이 기존의 측방가압충전법 보다는 효과적인 것으로 나타났다.

• Restorative Dentistry and Endodontics
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• v.27 no.3
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• pp.290-298
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• 2002

3차원적으로 잘 충전된 근관은 치근단 누출과 재감염을 방지하며, 조직이 잘 치유될 수 있는 생물학적 환경을 제공해준다. 이 때문에 근관계의 완전한 충전은 근관치료의 중요한 목표 중의 하나이다. 본 연구의 목적은 4가지 방법으로 근관충전 후 디지털 방사선 사진을 촬영하여 근관충전의 질을 평가하고 투명표본을 제작하여 색소침투범위를 측정함으로써, 근관충전방법에 따른 치근단부 폐쇄능을 비교 평가하고자 하는 것이다. 직선형의 단근관을 갖는 80개의 전치를 선택하여 ProFile$^{\circledR}$ 니켈-티타늄 회전식 기구를 사용하여 근관을 성형한 후 무작위로 20개씩 4군으로 나누었다. 사용된 근관충전법은 다음과 같다：MicroSeal$^{\circledR}$(Group A), Thermafil$^{\circledR}$(Group B), Continuous wave 충전법(Group C), 측방가압충전법(Group D), 각 군에서 10개 치아는 Sealapex를, 나머지 10개 치아는 AH26$^{\circledR}$을 충전용 시멘트로 사용하였다. 근관충전이 끝난 치아는 충전의 질과 길이를 평가하기 위해, 근원심과 협설방향으로 디지털 방사선 사진을 이용하여 촬영하였다. 각 치아의 치근단부 2mm를 제외한 나머지 부위는 두겹의 nail varnish를 바르고, 2% methlylene blue용액에 48시간동안 침잠시켰다. 흐르는 물에 깨끗이 세척한 후, 투명치아를 만들었다. 선상의 색소침투를 관찰하고 치관측 최대깊이를 입체현미경하에서 40배율로 평가하여 다음과 같은 결과를 얻었다. 1. 충전방법에 따른 근단부 폐쇄효과를 비교시, 실험군 모두 비교적 양호한 근단부 폐쇄효과를 보였고 통계학적으로 유의성이 없었다. 2. 충전용 시멘트에 따른 근단부 폐쇄효과를 비교시, AH26$^{\circledR}$을 사용한 군에서 Sealapex를 사용한 군보다 더 적은 색소침 투를 나타냈다(p<0.05). MicroSeal$^{\circledR}$을 이용한 실험 1군내에서 AH26$^{\circledR}$을 사용하였을 때 미세누출이 더 적었고(p<0.05), 다른 군내에서는 통계학적으로 유의성이 없었다. 3. 근단부 충전상태에 따른 미세누출 비교시, 저충전, 과충전과 색소침투간에는 상관관계가 없었다. 4.충전방법에 따른 근단부 충전상태 평가시, Thermafil$^{\circledR}$을 이용한 실험 2군에서 과충전이 많이 나타났다(p<0.05). 이상의 결과로, 기존의 측방가압법 및 여러 열가소성 충전법이 유사한 근단부 폐쇄효과를 나타낸 바, 방법에 따른 술자의 숙련도, 충전시간, 재근관치료의 편이성 등을 고려하여 근관충전방법을 선택하는 것이 합리적일 것이라고 사료된다.

• Restorative Dentistry and Endodontics
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• v.25 no.4
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• pp.536-542
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• 2000

임상에서 점차 Mineral Trioxide Aggregate (MTA)에 대한 우수성이 소개되면서, apical matrix로의 사용은 주목할 만하다 할 수 있다. 본 연구의 목적은 개방형근관에서 MTA가 apical matrix로 사용될 때의 치근단 밀폐효과를 알아 보고, 근관충전의 시기와 matrix의 두께가 치근단 밀폐에 미치는 영향을 치근단 미세누출의 측면과 matrix탈락빈도의 측면에서 관찰하고자 하는 것이다. 개방형 근관을 재현하고자 45개의 발거된 단근치에 #90크기로 근단공을 형성하였고, 투명레진등을 이용하여 치근단 병소를 갖는 치조골을 재현한 후, 4개의 실험 군과 1개의 대조 군으로 분류하였다. A군: 2mm두께의 MTA matrix 형성후, 열연화된 Gutta-percha와 AH26 sealer를 이용하여 즉시 근관충전. B군: 2mm 두께의 MTA matrix 형성후, A군과 같은 방법으로 24시간 후 근관충전. C군: 4mm 두께의 MTA matrix 형성후, A군과 같은 방법으로 즉시 근관충전. D군: 4mm 두께의 MTA matrix 형성후, A군과 같은 방법으로 24시간 후 근관충전. 대조군: matrix를 사용하지 않고 열연화된 Gutta-percha와 AH26 sealer를 이용하여 근관충전하였다. Matrix의 탈락이 있는 경우 기록하고 완전 수세 후 다시 시행하였다. 색소침투정도의 평가를 위해 methylene blue에 치아를 48시간 침수시킨 후 협설로 양분하였다. 각 시편들을 고배율 현미경 관찰 후 비디오촬영 하였고, digitalized image analysing program을 이용하여 두명의 관찰자가 누출의 정도를 평가한 후, One-way ANOVA로 통계적 유의성을 검증하여 다음과 같은 결과를 얻었다. 1. Matrix를 사용한 실험 군이 matrix를 사용하지 않은 대조 군에 비해 유의성 있게 낮은 누출을 보였다(p<0.05). 그러나 근관충전시기와 matrix의 두께를 달리한 실험군 내에서는 누출에 유의성 있는 차이가 나타나지 않았다. 2. 모든 실험군에서 gutta-percha를 이용한 근관충전의 시기에 matrix탈락 및 gutta-percha의 압출은 발생하지 않았다.

• The Journal of the Korean dental association
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• v.30 no.9 s.280
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• pp.687-691
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• 1992

• Restorative Dentistry and Endodontics
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• v.15 no.2
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• pp.46-57
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• 1990

The purpose of this study was to spectrophotometrically investigate the sealing effect of the ultrasonic canal obturation with softened gutta-percha utilizing an endosonic plugger by means of ultrasonic vibrations and heat. The 120 extracted human central and lateral incisors with single root were randomly selected, and the root canals were instrumented up to size #60 file by conventional method. The prepared canals were obtruated with gutta-percha by lateral condensation method, McSpadden technique and ultrasonic condensation method, with or without sealer. All specimens were immersed in 2% methylene blue in an incubator at $37^{\circ}C$ for 10 days. The teeth were then dissolved in 5ml of 60% nitric acid solution and the dye present within the root canal system was returned to solution. The leakage of dye was quantitatively measured via spectrophotometric method. The obtained data statistically evaluated usint two-way ANOVA and Student's t-test. The results were as follows : No statistically significant difference in leakage was observed between the lateral condensation method and ultrasonic condensation method, with and without sealer. When sealer was used or not, McSpadden technique showed significantly greater leakage than lateral or ultrasonic condensation method. Statistical analysis of the data indicated that the canals obturated in conjunction with sealer demonstrated less dye leakage than the canals obturated without sealer(p<0.01), except McSpadden technique. The ultrasonic condensation method appeared comparable sealing ability to the lateral condensation method.

• Restorative Dentistry and Endodontics
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• v.31 no.4
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• pp.323-329
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• 2006

The aim of this study was to evaluate the retrievability of Resilon as a root canal filling material Twenty-seven human single-rooted extracted teeth were instrumented utilizing a crown down technique with Gates-Glidden burs and ProFile system. In group1 (n = 12) canals were obturated with gutta percha and AH-26 plus sealer using a continuous wave technique and backfilled. In group 2 (n = 15) Resilon was used as a filling material. Then teeth were sealed and kept in $37^{\circ}C$ and 100% humidity for 7 days. For retreatment, the samples were re-accessed and filling material was removed using Gates-Glidden burs and ProFiles. Teeth were sectioned longitudinally to compare the general cleanliness and amount of debris $({\times}\;75)$ using SEM. Chi-square test was used $({\alpha}\;=\;0.05)$ to analyze the data. The total time required for removal of filling materials was expressed as mean ${\pm}SD$ (min) and analyzed by the Student t-test $({\alpha}\;=\;0.05)$, Required time for retreatment was $3.25\;{\pm}\;0.32$ minutes for gutta percha/ AH 26 plus sealer and $3.05\;{\pm}\;0.34$ minutes for Resilon. There was no statistically significant difference between the two experimental groups. There was no significant difference between the groups in the cleanliness of the root canal wall. This study showed that Resilon was effectively removed by Gates-Glidden burs and ProFiles.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.4
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• pp.213-221
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• 2022

Purpose: The efficacy of the amount of sealer in the root canal and two retreatment NiTi file systems in removing filling materials. Materials and Methods: Extracted premolars with a single root canal were selected for this study. After access opening and root canal preparation up to size #40/.06, the specimens were randomly divided into four groups. Gutta percha (GP) tapers of .06 or .04 were used for each group and filled using a single-cone filling technique with CeraSeal, a calcium silicate-based sealer. Each group was retreated either using the ProTaper Universal Retreatment System (PTUR) or the Hyflex Remover (HR). The time taken to remove the filling material, the amounts of apically extruded debris, and canal cleanliness were measured and compared. Results: The amount of sealer did not affect the efficiency when removing the filling materials. However, the filling material was removed faster in the HR group than in the PTUR group. Two types of NiTi files showed similar retreatment effects in the amounts of apically extruded debris and in the degree of canal cleanliness. Conclusion: The amount of sealer in canal filling had no significant effect on retreatability. Retreatment with HR removed filling materials is faster than PTUR. There was no difference in other removal efficiencies according to the type of retreatment NiTi file.

• Restorative Dentistry and Endodontics
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• v.30 no.5
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• pp.385-392
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• 2005

The purpose of this study was to observe the effect of canal filling on the bacteria left in the dentinal tubules and to compare the sealing ability between Gutta-percha and Resilon. The bovine dentin block models were prepared E. faecalis was inoculated to dentin blocks and incubated. The dentin blocks were divided into 5 groups. Group 1 was the negative control. Group 2 was the positive control. Group 3 was filled with ZOE based sealer and Gutta-percha, Group 4 with resin based sealer and Gutta-percha, and Group 5 with resin based sealer and Resilon. After 24 hour, the blocks were incubated at $37^{\circ}C$ for 1, 2, 3 and 4 weeks on BHI agar plates. The internal dentin portion of the blocks was removed using ISO 027, 029, 031, 035 round burs and the dentin chips were incubated at $37^{\circ}C$ for 24 hour Following incubation, the optical density of the medium was measured. The data were statistically analysed using repeated measures ANOVA and one-way ANOVA. The results were as follows, 1. There. was statistically significant reduction in the number of E. faecalis of the group where dentinal tubules were completely sealed with nail varnish in comparison with the groups obturated with gutta-percha or resilon (p < 0.05). 2. In group 5, the number of E. faecalis in the dentinal tubules decreased significantly with time (p < 0.05). whereas in Group 3 and 4, there was no reduction in its number (p > 0.05). 3. Under the conditions of this experiment, E. faecalis survived up to 4 weeks after obturation with gutta-percha or resilon (p > 0.05).

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.2
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• pp.129-136
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• 2016

The purpose of this study is to examine the sealing effect and efficiency of root canal filling MTA (Endoseal, Endoseal MTA). A total of 106 extracted single rooted teeth were used and classified with group AH (AH-26), group PR (ProRoot MTA), group ES (Endoseal) and group EM (Endoseal MTA) depending on filled sealers. Time was measured in each group when sealers were filled. The groups were divided into subgroup A and subgroup B. The sealing of root canal walls and penetration of sealer in the dentinal tubule were evaluated, respectively. According to the results, the sealing of root canal walls and dentinal tubule penetration of root canal filling MTA were inferior to AH-26 (p < 0.05). When compared with ProRoot MTA, however, there was no significant difference in sealing of root canal walls (p > 0.05), but dentinal tubule penetration was high (p < 0.05). Working time was shorter in root canal filling MTA than ProRoot MTA and AH-26 (p < 0.05). In conclusion, root canal filling MTA has lower root canal sealing effect than resin-based sealer, however, when in MTA needed root canal filling, it could be an effective alternative.

• Restorative Dentistry and Endodontics
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• v.19 no.2
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• pp.429-446
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• 1994

The purpose of this study was to evaluate the sealing effect of warm lateral condensation technique by Endotec spreader, comparing with other canal filling techniques. One hundred and forty extracted human teeth with single canal were instrumented and randomly divided into four groups according to canal filling techniques including lateral condensation with sealer, warm lateral condensation with sealer, warm lateral condensation without sealer, and injection-molded thermoplasticized gutta-percha without sealer. Obturated canals were exposed to 2 % methylene blue solution at $37^{\circ}C$ for 24 hours and measurement of the degree of microleakage was done linearly and volumetrically with stereozoom microscope and UV-spectrophotometer respectively. The results were as follows ; When sealer was used, the canals obturated by warm lateral condensation showed less leakage linearly and volumetrically than the canals obturated by standard lateral condensation with no statistically significant difference. The obturated canals by warm lateral condensation with sealer showed less leakage linearly and volumetrically than the canals obturated by warm lateral condensation without sealer and by injection-molded thermoplasticized gutta-percha without sealer with statistical significance (p<0.05). No statistical difference revealed that the group filled with the use of the Endotec had significantly less leakage than any of the other groups. There was a significant correlation between the linear measurement and volumetric measurement(r=0.4459, p<0.05).