• Title/Summary/Keyword: Prompt NO

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혈액 오염된 역충전 재료의 미세누출 평가 (Evaluation of Microleakage with Retrograde Filling Materials in Blood Contamination)

  • 조혜진;문종현;박종적;유미경
    • 구강회복응용과학지
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    • 제23권1호
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    • pp.85-93
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    • 2007
  • The purpose of this study was to evaluate the microleakage of root-end filling material filled in blood contaminated root-end cavity and self-etching adhesive placed over blood contaminated resected root apices without root-end preparation. Extracted, human maxillary incisors, canines and mandibular premolar were randomly divided into four groups of 15 teeth each. After canal preparation, resection of the apex and root-end preparation, MTA and IRM were filled in the root-end cavity (A and B group). After canal preparation and resection of the apex, Clearfil SE Bond and Prompt L-Pop were applied over the contaminated root-end surfaces (C and D group). The roots were then subjected to 15cm of water pressure to simulate periapical microleakage stress. Data were analyzed using one-way ANOVA. The results were as follows : 1. All groups showed a tendency of decreasing microleakage in process of time after 2weeks later except IRM group. 2. After 2 weeks and 1 month, MTA group showed less microleakage significantly than other groups(p<0.05). After 2 months, Prompt L-Pop group showed less microleakage significantly than other groups(p<0.05). 3. After 9 months, there were no significant differences among four groups(p>0.05). Thus it is considered that apical sealing using adhesives system without root-end preparation is good method in endodontic surgery.

Er:YAG 레이저를 조사한 유치 상아질의 전단결합강도에 관한 연구 (A STUDY OF SHEAR BOND STRENGTH OF ER:YAG LASER-IRRADIATED PRIMARY DENTIN)

  • 이진화;김종수;유승훈
    • 대한소아치과학회지
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    • 제34권4호
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    • pp.569-578
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    • 2007
  • 본 연구는 자가 부식과 two-bottle system에 의한 레진 부착시 레이저와 일반 고속 핸드피스에 의한 치아형성 관계를 규명해보고자 하였다. 55개의 유치를 발거한 후 레진에 매몰하여 상아질을 노출시켜 시편을 준비하였고 다음과 같이 분류하였다. I군은 고속핸드피스로 치아 형성 후 $Adper^{TM}$ $Prompt^{TM}$ L-$Pop^{TM}$(3M Unitek, USA)을, II군은 Er:YAG 레이저로 치아 형성 후 $Adper^{TM}$ $Prompt^{TM}$ L-$Pop^{TM}$(3M Unitek, USA)을, III군은 레이저로 형성 후 산부식과 $Adper^{TM}$ Single Bond Plus Adhesive(3M Unitek, USA)를, IV군은 레이저로 형성 후 산부식 없이 $Adper^{TM}$ Single Bond Plus Adhesive(3M Unitek, USA)를 적용하였고 V군은 고속 핸드피스로 치아 형성 후 산부식과 $Adper^{TM}$ Single Bond Plus Adhesive(3M Unitek, USA)를 적용하였다. 레진 $Filtek^{TM}$ Z250(3M Unitek, USA)을 직경 1.5 mm, 길이 3 mm의 투명관에 충전 후 적용하였다. 각 그룹 시편의 전단강도를 측정하였고 레이저와 고속 핸드피스로 치아 형성 후와 각각 산부식을 한 후 주사전자 현미경으로 관찰한 결과 다음과 같은 결론을 얻었다. 1. 기존 방법인 고속 핸드피스를 이용한 치아 형성 후 산부식과 $Adper^{TM}$ Single Bond를 이용한 방법이 가장 높은 결합 강도를 보였다. 2. 레이저를 이용한 치아 형성 후 산부식을 하지 않고 $Adper^{TM}$ Single Bond를 이용한 방법은 가장 낮은 결합 강도를 보였다. 3. 고속 핸드피스를 이용한 치아 형성 후 $Prompt^{TM}$ L-$Pop^{TM}$을 이용한 레진 부착을 한 그룹과 레이저를 이용해 치아를 형성한 이후 산부식과 $Adper^{TM}$ Single Bond를 이용한 방법간의 결합 강도는 유의한 차이를 나타내지 않았다. 4. 레이저를 이용한 치아 형성 후 $Prompt^{TM}$ L-$Pop^{TM}$을 이용한 II군은 I, III, V군에 비해서는 결합강도가 낮았으나 IV군에 비해서는 결합강도가 유의성 있게 높았다. 5. 주사전자 현미경 관찰시 레이저로 치아 형성한 상아질 표면은 불규칙한 표면이 두드러졌으며 도말층이 제거되었음을 볼 수 있었고 산부식 후에는 불규칙한 부위가 줄어들고 상아세관이 커짐을 확인했다.

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2-D LIF를 이용한 층류화염의 NO 생성특성에 관한 연구 (A Study of NO Formation Characteristics in Laminar Flames Using 2-D LIF Technique)

  • 이원남;차민석;송영훈
    • 한국연소학회지
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    • 제8권3호
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    • pp.38-48
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    • 2003
  • OH, CH and NO radical distributions have been measured and compared with the numerical analysis results in methane/air partially premixed laminar flames using 2-D LIF technique. The pick intensity of OH LIF signal is insensitive to fuel equivalence ratio: however, CH LIF intensity decreases as equivalence ratio increases and the NO concentration increases with equivalence ratio. The contribution of the prompt NO, formed near premixed reaction zone, to the total NO formation is evident from the OH, CH, and NO PLIF images in which the dilution effect of nitrogen is minimal for the highest equivalence ratio. Measured OH and NO LIF signals in counterflow flames agree with the computed concentration distributions. Both numerical and experimental results indicate that the structural change in a flame alters the NO formation characteristics of a partially premixed counterflow flame. The nitrogen dilution also changes flame structure, temperature and OH radical distributions and results in the decreased NO concentrations in a flame. The levels of decrease in NO concentrations, however, depends on the premixedness(${\alpha}$) of a flame. The larger change in the flame structure and NO concentrations have been observed in a premixed flame(${\alpha}=1.0$), which implies that the premixedness is likely to be a factor in the dilution effect on NO formation of a flame.

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Reconsideration of urine culture for the diagnosis of acute pyelonephritis in children: a new challenging method for diagnosing acute pyelonephritis

  • Lee, Jun Ho;Rhie, Seonkyeong
    • Clinical and Experimental Pediatrics
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    • 제62권12호
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    • pp.433-437
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    • 2019
  • Acute pyelonephritis (APN) should be detected and treated as soon as possible to reduce the risk of the development of acquired renal scarring. However, in the medical field, urine culture results are not available or considered when the prompt discrimination of APN is necessary and empirical treatment is started. Furthermore, urine culture cannot discriminate APN among children with febrile urinary tract infection (UTI) (pyelitis, lower UTI with other fever focus). Therefore, the usefulness of urine culture for diagnostic purposes is small and the sampling procedure is invasive. Congenital hypoplastic kidney is the most common cause of chronic kidney injury in children. Thus, it is desirable that a main target be detected as early as possible when imaging studies are performed in children with APN. However, if APN does not recur, no medical or surgical treatment or imaging studies would be needed because the acquired renal scar would not progress further. Therefore, the long-term prognosis of APN in young children, particularly infants, depends on the number of recurrent APN, not other febrile UTI. New methods that enable prompt, practical, and comfortable APN diagnosis in children are needed as alternatives to urinary catheterization for urine culture sampling.

치수압이 상아질 접착제의 미세전단 결합강도에 미치는 영향에 관한 In vitro 연구 (MICRO-SHEAR BOND STRENGTH TO DENTIN UNDER SIMULATED PULPAL PRESSURE)

  • 송윤정;박성호
    • Restorative Dentistry and Endodontics
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    • 제29권4호
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    • pp.339-345
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    • 2004
  • The aim of this study was to measure and compare the micro shear bond strengths of the following dentin bonding systems to the dentin surfaces under simulated pulpal pressure: All Bond $2^{\circledR},{\;}Second^{\circledR},{\;}AdheSE^{\circledR}$, Adper Prompt $L-Pop^{\circledR}$. The occlusal surfaces of 180 extracted human molars were prepared so the dentin bonding surfaces could be exposed. The teeth were randomly assigned to 3 equal groups of 60 each and subdivided. The dentin surfaces were treated with the above mentioned bonding system and resin composite cylinders were built up under a simulated pulpal pressure when saline (Group II) or diluted bovine serum (Group III) was used as the pulpal fluid. As a control. the same procedures were performed in the dried dentin surfaces (Group I). After one day of storage in water. the micro shear bond strengths were measured using an EZ tester. Group II and III showed significantly lower shear bond strength than Group I statistically (p < 0.05). $SEbond^{\circledR}{\;}and{\;}AdheSE^{\circledR}$ showed no difference among the different dentin condition. In the Adper Prompt $L-Pop^{\circledR}$. a simulated pulpal pressure were applied to the specimens using diluted bovine serum. which showed a higher strength than the specimens in which saline was used (p < 0.05).

$CO_2$ 첨가가 $CH_4$-공기 대향류 확산화염의 구조 및 NOx 생성에 미치는 영향 (Effect of $CO_2$ Addition on Flame Structure and NOx Formation of $CH_4-Air$ Counterflow Diffusion Flames)

  • 이승로;한지웅;이창언
    • 한국연소학회지
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    • 제4권2호
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    • pp.97-108
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    • 1999
  • This numerical study was to investigate the effect of $CO_2$ addition on the structures and NOx formation characteristics in $CH_4$ counterflow diffusion flame. The importance of radiation effect was identified and $CO_2$ addition effect was investigated in terms of thermal and chemical reaction effect. Also the causes of NOx reduction were clarified by separation method of each formation mechanisms. The results were as follows : The radiation effect was intensified by $CO_2$ addition. Thermal effect mainly contributed to the changes in flame structure and the amount of NO formation but the chemical reaction effect also cannot be neglected. The reduction of thermal NO was dominant with respect to reduction rate, but that of prompt NO was dominant with respect to total amount.

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Effect of 38% carbamide peroxide on the microleakage of silorane-based versus methacrylate-based composite restorations

  • Hashemi Kamangar, Sedighe Sadat;Ghavam, Maryam;Mahinfar, Nazanin;Pourhashemi, Seyed Jalal
    • Restorative Dentistry and Endodontics
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    • 제39권3호
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    • pp.172-179
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    • 2014
  • Objectives: This study aimed to assess the effect of 38% carbamide peroxide on the microleakage of class V cavities restored with either a silorane-based composite or two methacrylate-based composites. Materials and Methods: A total of 96 class V cavities were prepared on the buccal surface of extracted human teeth with both enamel and dentin margins and were randomly assigned into three groups of Filtek P90 (3M-ESPE) + P90 system adhesive (3M-ESPE)(group A), Filtek Z250 (3M-ESPE) + Adper Prompt L-Pop (3M-ESPE)(group B) and Filtek Z350XT (3M-ESPE) + Adper Prompt L-Pop (group C). Half of the teeth were randomly underwent bleaching (38% carbamide peroxide, Day White, Discus Dental, applying for 15 min, twice a day for 14 day) while the remaining half (control) were not bleached. Dye penetration was measured following immersion in basic fuchsine. Data were statistically analyzed using Kruskal-Wallis and Mann-Whitney U tests at a level of 0.05. Results: No significant differences were found between composites in the control groups in enamel (p = 0.171) or dentin (p = 0.094) margins. After bleaching, microleakage of Z250 (in enamel [p = 0.867] or dentin [p = 0.590] margins) and Z350 (in enamel [p = 0.445] or dentin [p = 0.591]margins) did not change significantly, but the microleakage of P90 significantly increased in both enamel (p = 0.042) and dentin (p = 0.002) margins. Conclusions: No significant differences were noted between the bleached and control subgroups of two methacrylate-based composites in enamel or dentin margins. Microleakage of silorane-based composite significantly increased after bleaching.

상아질접착제와 열순환에 따른 유동성 레진의 전단결합강도 비교 연구 (A COMPARATIVE STUDY OF SHEAR BOND STRENGTH OF FLOWABLE RESIN ASSOCIATED WITH DENTIN ADHESIVE SYSTEMS WITH THERMOCYCLING EFFECT)

  • 남기영
    • 대한치과보철학회지
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    • 제44권4호
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    • pp.383-393
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    • 2006
  • Statement of problem : Limited research on flowable resin has been undertaken on its application directly on dentin associated with the adhesive systems. Purpose : This study was to evaluate the shear bond strengh and fracture aspect of flowable resin on human dentin with various types of dentin bonding adhesives with thermo cycling effect. Materials and methods: Filtek-Flow(3M ESPE, USA) was used as flowable resin and Eighty human molars were randomly divided into 4 groups : three dentin bonding adhesives (Scotchbond-Multipurpose : 3-step contentional system, One-Step : One-bottle system. Prompt L-Pop : All-in-one, self-etching primer) and 32% etching treatment without bonding adhesive as a control group. For evaluating their durability of bonding, each group was subdivided : storaging in the water at 37$^{\circ}C$(24 hours) and thermocycling (0$^{\circ}C$-55$^{\circ}C$, 30 seconds intervals, 1000 cycle). Shear bond strength tests were performed and resin-dentin interface and fracture mode were observed. Results were analysed by one-way ANOVA and Scheffe's multiple range test. Results and Conclusion : 1. At 0 cycle, the mean shear bond strength of One-Step exhibited the highest value of all groups(p<0.05), and there were no significant differences between Prompt L-Pop and Scotchbond-Multipurpose, Scotchbond-Multipurpose and control(p>0.05). After 1000 thermocycling, One-Step exhibited higher value than other groups(p<0.05), and there were no significant differences among other groups (p>0.05). 2. The shear bond strength of each group was significantly decreased after thermocycling except Scotchbond-Multipurpose (p>0.05). 3. The most common failure mode was adhesive type and mixed type, next in order.

메탄-공기 대향류확산화염에서 $CO_2$$H_2O$의 첨가가 화염구조와 NOx배출특성에 미치는 화학적 영향 (Chemical effects of added $CO_{2}$ and $H_{2}O$ to major flame structures and NOx emission characteristics in $CH_4$/Air Counterflow Diffusion Flames)

  • 황동진;박정;이경환;길상인
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 제26회 KOSCO SYMPOSIUM 논문집
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    • pp.129-136
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    • 2003
  • Numerical study with momentum-balanced boundary conditions has been conducted to grasp chemical effects of added $CO_{2}$ and $H_{2}O$ to fuel- and oxidizer-sides on flame structure and NO emission behavior in $CH_{4}$/Air counterflow diffusion flames. The dilution with $H_{2}O$ results in significantly higher flame temperatures and NO emission, but dilution with $CO_{2}$ has much more chemical effects than that with $H_{2}O$. Maximum reaction rate of principal chain branching reaction due to chemical effects decreases with added $CO_{2}$. but increases with added $H_{2}O$. The NO emission behavior is closely related to the production rate of OH, CH and N. The OH radical production rate increases with added $H_{2}O$ but those of CH, N decrease. On the other hand the production rates of OR CH and N decrease with added $CO_{2}$. It is found that NO emission behavior is considerably affected by chemical effects of added $CO_{2}$ and $H_{2}O$.

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Eulerian Particle Flamelet Modeling for Combustion Processes of Bluff-Body Stabilized Methanol-Air Turbulent Nonpremixed Flames

  • Kim, Seong-Ku;Kang, Sung-Mo;Kim, Yong-Mo
    • Journal of Mechanical Science and Technology
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    • 제20권9호
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    • pp.1459-1474
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    • 2006
  • The present study is focused on the development of the RIF (Representative Interactive Flamelet) model which can overcome the shortcomings of conventional approach based on the steady flamelet library. Due to the ability for interactively describing the transient behaviors of local flame structures with CFD solver, the RIF model can effectively account for the detailed mechanisms of $NO_x$ formation including thermal NO path, prompt and nitrous $NO_x$ formation, and reburning process by hydrocarbon radical without any ad-hoc procedure. The flamelet time of RIFs within a stationary turbulent flame may be thought to be Lagrangian flight time. In context with the RIF approach, this study adopts the Eulerian Particle Flamelet Model (EPFM) with mutiple flamelets which can realistically account for the spatial inhomogeneity of scalar dissipation rate. In order to systematically evaluate the capability of Eulerian particle flamelet model to predict the precise flame structure and NO formation in the multi-dimensional elliptic flames, two methanol bluffbody flames with two different injection velocities are chosen as the validation cases. Numerical results suggest that the present EPFM model has the predicative capability to realistically capture the essential features of flame structure and $NO_x$ formation in the bluff-body stabilized flames.