• Restorative Dentistry and Endodontics
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• 제43권1호
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• pp.11.1-11.10
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• 2018

Objectives: This study aimed to introduce the use of laser-induced breakdown spectroscopy (LIBS) for evaluation of the mineral content of root canal dentin, and to assess whether a correlation exists between LIBS and scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) methods by comparing the effects of irrigation solutions on the mineral content change of root canal dentin. Materials and Methods: Forty teeth with a single root canal were decoronated and longitudinally sectioned to expose the canals. The root halves were divided into 4 groups (n = 10) according to the solution applied: group NaOCl, 5.25% sodium hypochlorite (NaOCl) for 1 hour; group EDTA, 17% ethylenediaminetetraacetic acid (EDTA) for 2 minutes; group NaOCl+EDTA, 5.25% NaOCl for 1 hour and 17% EDTA for 2 minutes; a control group. Each root half belonging to the same root was evaluated for mineral content with either LIBS or SEM/EDS methods. The data were analyzed statistically. Results: In groups NaOCl and NaOCl+EDTA, the calcium (Ca)/phosphorus (P) ratio decreased while the sodium (Na) level increased compared with the other groups (p < 0.05). The magnesium (Mg) level changes were not significant among the groups. A significant positive correlation was found between the results of LIBS and SEM/EDS analyses (r = 0.84, p < 0.001). Conclusions: Treatment with NaOCl for 1 hour altered the mineral content of dentin, while EDTA application for 2 minutes had no effect on the elemental composition. The LIBS method proved to be reliable while providing data for the elemental composition of root canal dentin.

• 대한화학회지
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• 제39권11호
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• pp.884-886
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• 1995

• 구강회복응용과학지
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• 제29권1호
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• pp.37-44
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• 2013

근관치료 후 적절한 치관부 밀폐를 위해 레진을 이용한 코어수복방법이 현재 많이 사용되고 있다. 하지만, 근관치료 과정에서 사용되는 NaOCl이나 EDTA같은 근관세척제는 레진 접착에 영향을 주는 것으로 알려져 있으며, 이에 관한 많은 연구들이 이루어져 왔다. 본 연구에서는 ethanol wet bonding을 치수강 상아질에 적용 시에 NaOCl과 EDTA가 결합강도에 미치는 영향에 대해 조사하였다. 30개의 인간 대구치로부터 총 60개의 시편을 얻었고, 이를 무작위로 4개의 군으로 분류했다. G1: 증류수로 세척후 증류수로 마무리 세척, G2: NaOCl로 세척 후 NaOCl로 마무리세척, G3: NaOCl로 세척 후 EDTA로 마무리세척, G4: NaOCl로 세척 후 EDTA로 마무리세척하고 접착과정에서 산부식과정 생략. 접착과정은 인산부식 후 에탄올의 농도를 50%, 70%, 80%, 95% 그리고 100%로 순차적으로 증가시켜가면서 상아질을 탈수시키고 에탄올에 적셔지도록 하였다. 프라이머는 HEMA가 포함되지 않은 상용화된 접착제인 ALL-BOND 3 RESIN과 에탄올을 반반씩 섞어 만들었다. 프라이머 적용 후 ALL-BOND 3 RESIN을 접착제로 사용하였다. 저점도 복합레진을 이용하여 6mm 두께로 적층충전한 후 빔 형태로 잘라 미세인장결합강도 실험을 하였다. NaOCl 처리한 그룹은 미세인장결합강도에 통계적으로 유의한 차이를 보여주지는 않았지만 낮은 평균값을 보여주었다(p=0.052). NaOCl 처리 후 1분간 EDTA로 처리한 그룹은 다른 그룹보다 유의하게 높은 결합강도를 보여주었다(p<0.05). EDTA 처리가 결합강도를 향상 시켰지만, 산부식 과정을 생략할 경우 유의하게 낮은 결합 강도를 보여주었으며, 이는 EDTA처리가 산부식 과정을 대신할 수는 없다는 것을 보여준다.

• Restorative Dentistry and Endodontics
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• 제40권2호
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• pp.143-148
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• 2015

Objectives: This study evaluated the maximum depth and percentage of irrigant penetration into dentinal tubules by passive ultrasonic irrigation (PUI). Materials and Methods: Thirty extracted human teeth were instrumented and divided into three groups. According to final irrigation regimen, 5.25% sodium hypochlorite (Group A, NaOCl), 2% chlorhexidine (Group B, CHX) and saline solution (Group C, control group) were applied with Irrisafe 20 tips (Acteon) and PUI. Irrigant was mixed with 0.1% rhodamine B. Sections at 2 mm, 5 mm, and 8 mm from the apex were examined with confocal laser scanning microscopy (CLSM). The percentage and maximum depth of irrigant penetration were measured. Kruskal-Wallis test and Mann-Whitney test were performed for overall comparison between groups at each level and for pairwise comparison, respectively. Within a group, Wilcoxon test was performed among different levels. p values less than 0.05 were considered significant. Results: In all groups, highest penetration depth and percentage of penetration were observed at the 8 mm level. At 2 mm level, Groups A and B had significantly greater depths and percentages in penetration than Group C (p < 0.05), but there were no significant differences between Groups A and B. At 5 mm level, penetration depths and percentage of penetration was not significantly different among the groups. Conclusions: NaOCl and CHX applied by PUI showed similar depth and percentage of penetration at all evaluated levels.

• Restorative Dentistry and Endodontics
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• 제7권1호
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• pp.65-69
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• 1981

This study was conducted to evaluate the cleansing effect of RC-Prep (10% Urea-peroxide, 15% EDTA) on apical third of root canal. Thirty single rooted human teeth were divided into three groups, and ten canals in each group were all enlarged three sizes greater than their original diameter with K-type files and irrigated with each of three irrigants. The three used irrigants were RC-prep (Premier Co.) in combination with 3.5% Sodium hypochlorite, Normal saline, 3.5% Na OCL. In each group, one of three irrigants were used in conjunction with instrumentation as they would be during clinical condition. After final irrigation, the canals were dried with paper points and the teeth were split longitudinally. The cleanness of canal walls iii the apical region were examined with Scanning Electron Microscope. The following results were drawn. 1. The use of Rc-Prep in combination with 3.5% NaOCl showed more clean canal surface than the use of other two irrigants. 2. The canals used RC-Prep in combination with 3.5% NaOCl revealed remnants of pulp tissue and smeared layer, but the openings of dentinal tubules were relatively clean and wide. 3. There was no significant difference in the debridement effect of 3.5% NaOCl and Saline solution. 4. The use of Saline solution showed great amount of remnants of pulp tissue which couldn't find in the use of 3.5% NaOCl.

• 대한치과의사협회지
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• 제56권10호
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• pp.556-566
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• 2018

Whether you use a hand file or an engine-driven file, you cannot remove bacteria completely from the root canal by mechanical work alone. If the root canal is well cleaned, endodontic irrigants will well penetrate into these areas that will not be mechanically accessible. It will decompose and remove the biofilm and also remove the smear layer to reach the dentinal tubule. Clinicians who are not yet using NaOCl as their primary irrigant, should be aware that there are no other irrigants that offer all the benefits of NaOCl and are inexpensive. Clinicians may be reluctant to use it because of concern about NaOCl accident, but this possibility is extremely low if used with caution.

• 아시안잔디학회지
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• 제2권1호
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• pp.41-48
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• 1988

Research was conducted to obtain easy and secure methods for promoting germination of Korean lawngrass (Zoysia japonic a Steud.) seed. The effect of sodium hypochiorite (NaOCl) treatment on germination of seeds was compared with that of potassium hydroxide (KOH) treatment under conditions of duration of seed storage after harvest and temperature of treatment. Emergence of seedlings from soil and micro-flora infection rate among seed treatments were investigated. 1. The promotion of germination was much more evident in seeds treated with 4% NaOCl for 8 and 10 hours than in seeds treated with 25% or 30% KOH for 30 and 40 minutes. Longer durations of storage before seed treatment in KOH than in NaOCl were required to initiate enough germination. 2. Differences in temperature of treatment with NaOCT did not have much influence on germination of seeds and treatment temperature of 15˚C was better than that of 200˚C and 300˚C for promoting germination. But seed treatment with KOH significantly promoted germination with increasing temperature of treatment from I 5˚C to 20˚C and 30˚C. 3. GA$_3$ treatment enhanced germination in NaOCl-pretreated seeds at early stage of imbibition and in-creased about 10% germination after 10 days of imbibition in KOH-pretreated seeds. 4. NaOC1 treatments significantly decreased the rate of the infection of microflora in seed samples and enhaced emergence of seedlings from soil compared with KOH treatment. 5. NaOC1 treatment had advantage over KOH treatment with respect to ease of preparing, securing and handling in stimulating germinating of Korean lawngrass seeds.

• 한국수산과학회지
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• 제29권5호
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• pp.595-602
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• 1996

식품 공장에서 일반적으로 사용하고 있는 살균제인 benzalkonium chloride (BAC)와 sodium hypochlorite (NaOCl)의 Listeria monocytogenes ATCC 15313에 대한 살균 효과를 알아보기 위하여 살균제에 균을 직접 현탁시킨 경우 (in vitro)와 sponge에 균을 접종하여 실험한 경우 (in vivo)를 비교하였다. 먼저 $0\~0.1\%$ BAC와 $0\~150ppm$ NaOCl (유효염소량)을 일정 농도로 조절하여 균을 현탁시킨 결과 BAC의 경우는 $0.25\%$ 이상의 농도에서 0.5분 이내에, 그리고 NaOCl은 100ppm에서 2분이내에 살균효과를 나타내었고 그 이상의 농도에서는 30초 이내에 살균효과를 나타내었다. 그리고 sponge $(6.0{\times}4.0{\times}4.0cm)$에 균 배양액 (약 $10^7\;CFU/ml$, tryptic soy broth) 15ml와 위의 2가지 살균제를 각각 일정 시간 처리한 결과 최초 20분 동안 살균효과가 좋았고 그 이후에는 효과가 감소하였다. BAC $0.1\%$ 이상부터 살균효과가 나타나 $0.25\%$의 경우 20분만에 3-log정도의 균수가 감소되었고 NaOCl도 300ppm 이상에서 살균효과가 나타나 800ppm의 경우 20분만에 3-log 정도의 균수가 감소되었다. 이 sponge를 실제 공장에 응용하기 위하여 modeling하여 살균제의 효과를 실험하였다. 즉 15ml의 배양액과 15ml의 살균제 $(0.25\%\;BAC,\;800ppm\;NaOCl)$를 20분 처리시킨후, 200ml의 멸균증류수로 씻은다음 꼰 짜서 TSB 100m1에 넣어 $5\~37^{\circ}C$에서 배양시키면서 균수의 변화를 관찰하였다. 두 살균제 모두 비슷한 양상을 나타내어 $5^{\circ}C$와 $15^{\circ}C의 경우는 1일 배양에 1-log정도 증가한다음 지속적으로 증식하였고 나머지의 경우도 온도가 높을수록 증식이 활발하였고 배양 $1\~3$일만에 $10^{9}CFU/ml$ 정도로 증식되었다.

• 한국식품조리과학회지
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• 제18권2호
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• pp.200-205
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• 2002

본 연구는 옥수수 전분의 기능 특성을 개선시키고자, 다양한 sodium hypochlorite(NaOCl)농도에서 산화시킨 산화 전분의 분자 구조적 변화에 대하여 시험하였다. 전분의 분자량 분포에서 산화 전분은 고분자량의 피크가 점차 작아지고 저분자량 부분의 피크가 높아져 전체적 분자량 분포가 낮은 쪽으로 이동하였고, 요오드 최대 흡수 파장이 감소되면서 색깔이 변화하였다. 무처리 전분은 온도가 증가함에 따라 분자량이 큰 부분의 용출이 증가하였다. 산화전분의 경우 아밀로펙틴이 산화에 의해 분해되어 전분 입자내에 큰 분자량을 가진 분자가 감소되면서 작은 분자량을 가지는 분자가 증가되기 때문에 가용성 탄수화물의 양이 증가하였다. DSC 특성에서는 상전이 온도 범위와 엔탈피의 차이는 없었으나 산화 전분이 무처리 전분보다 노화경향이 더 크게 나타났다. 산화전분용액의 광투과도는 증가하였다.

• Restorative Dentistry and Endodontics
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• 제43권2호
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• pp.14.1-14.16
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• 2018

Objectives: The aim of this systematic review was to critically analyze previously published studies of the effects of dentin surface pretreatment with deproteinizing agents on the bonding of self-etch (SE) adhesives to dentin. Additionally, a meta-analysis was conducted to quantify the effects of the above-mentioned surface pretreatment methods on the bonding of SE adhesives to dentin. Materials and Methods: An electronic search was performed using the following databases: Scopus, PubMed and ScienceDirect. The online search was performed using the following keywords: 'dentin' or 'hypochlorous acid' or 'sodium hypochlorite' and 'self-etch adhesive.' The following categories were excluded during the assessment process: non-English articles, randomized clinical trials, case reports, animal studies, and review articles. The reviewed studies were subjected to meta-analysis to quantify the effect of the application time and concentration of sodium hypochlorite (NaOCl) and hypochlorous acid (HOCl) deproteinizing agents on bonding to dentin. Results: Only 9 laboratory studies fit the inclusion criteria of this systematic review. The results of the meta-analysis revealed that the pooled average microtensile bond strength values to dentin pre-treated with deproteinizing agents (15.71 MPa) was significantly lower than those of the non-treated control group (20.94 MPa). Conclusions: In light of the currently available scientific evidence, dentin surface pretreatment with deproteinizing agents does not enhance the bonding of SE adhesives to dentin. The HOCl deproteinizing agent exhibited minimal adverse effects on bonding to dentin in comparison with NaOCl solutions.