• 한국산학기술학회논문지
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• 제5권4호
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• pp.279-281
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• 2004

100%천연향을 이용하여 제작, 개발된 해충기피제의 기피력을 테스트하였다. 해충기피제를 착용한 그룹과 착용하지 않은 그룹으로 구분하여 실험실에서 사육한 모기와 서해안에 위치한 몽산포 해수욕장, 동해안에 위치한 낙산 및 설악 해수욕장과 천안에 있는 태조산에서 해충에 대한 기피력을 측정하였으며, 각 그룹별로 5명씩 5회에 걸쳐 각 회당 1시간동안에 흡혈개체로부터 물린 갯수를 확인하여 이들의 평균값을 계산하였다. 그 결과, 실험실에서는 91%,몽산포 해수욕장에서는 78%, 낙산 및 설악 해수욕장에서는 93%, 태조산에서는 90%의 기피력을 보여주었으며, 이는 상당히 탁월한 기피효과를 나타내었다.

• Mass Spectrometry Letters
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• 제9권4호
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• pp.110-114
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• 2018

Since accumulation of chemicals in deciduous teeth can occur from the second trimester of fetal development to shedding, a deciduous tooth has been considered as an attractive biomatrix for estimating individual chemical exposures recently. Therefore, detection of organic chemicals from teeth has received an increasing attention in exposomics research. Most previous studies on organic chemical analysis of teeth not only focused on a few targeted chemicals but also ignored potential contaminants from an enamel surface or a dental pulp. Recently, our group started developing a multi-class organic analysis method for deciduous teeth and tried to find a proper incubation condition of tooth materials. Our results showed that incubation with methanolic HCl provided the best performance among tested.

• 대한소아치과학회지
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• 제30권3호
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• pp.465-470
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• 2003

소아에서 영구 전치부에 강한 외상이 가해지는 경우 단순한 수평파절보다는 비스듬한 수직-수평파절을 보이는 경우가 많으며 파절선이 치은연하로 위치되는 경우도 많은데 그러한 경우 최근에 의도적 재식술을 이용한 치료가 많이 시도되고 있다. 파절치를 탈구시킨 후 순설측을 뒤바꿔서 재식할 경우치근의 방향 차이로 인하여 발치와에서 상방으로 위치되면서 치관의 길이를 증가시킬 수 있으며 파절선을 순측에 위치시켜 시야확보를 용이하게 할 수 있다. 본 증례에서는 치아외상으로 상악 중절치가 치관-치근 파절된 혼합치열기 환아에서 파절치를 $180^{\circ}$ 회전시켜 의도적 재식술을 시행하여 치료한 후 양호한 결과를 얻었다. 이에 예전의 치료방법과 더불어 회전을 이용한 의도적 재식술은 치관-치근 파절치의 또다른 치료 방법이 되리라 사료된다.

• 대한소아치과학회지
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• 제36권2호
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• pp.310-317
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• 2009

치외치는 치아의 교합면에 부가적인 교두나 돌기(tubercle)를 가진 치아의 형태 이상이다. 치외치는 1-4%의 유병율을 보이며 하악 소구치에서 발생 빈도가 높다 치외치의 돌기는 쉽게 마모되거나 파절되어 치수 노출, 치수 생활력 상실, 안면부 감염, 골수염 등을 일으킬 수 있다. 또한, 돌기가 파절될 때 치외치의 치근단이 미성숙 상태인 경우가 많아 근관 치료가 쉽지 않다. 미성숙 영구치의 근관치료 시 수산화칼슘이 널리 사용되어 왔으나 내원 빈도 단축을 위해 여러 대체 재료들이 제안되어 왔다. 그 중 하나인 Mineral Trioxide Aggregate는 우수한 생체적합성과 변연 폐쇄성을 특징으로 하며, 미성숙 영구치의 근관치료 시 치료 기간을 단축시킬 수 있다. 본 증례보고에서는 치외치로 인한 치수 괴사로 봉와직염이 발생한 환자를 Mineral Trioxide Aggregate로 치료하였다. 미성숙 치근단을 가진 하악 소구치에 Mineral Trioxide Aggregate를 이용한 치근단형성술(apexification)을 시행하여 임상적 및 방사선학적으로 양호한 결과를 얻었으며, 한 증례에서는 치근단유도술(apexogenesis)의 결과와 같이 계속적인 치근 성장이 관찰되었다.

• 대한소아치과학회지
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• 제24권4호
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• pp.781-787
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• 1997

In spite of the improvements of the techniques in the field of preventive dentistry, many children still present with extensive destruction of primary anterior teeth. Not only the practioner must consider the pulp state of the primary incisor, but also restore the form, function and esthetics of the tooth. Restorative treatment of primary incisor tooth requires durability, retention and esthetics. Stainless steel crowns used in restoring primary anterior teeth is retentive and durable in comparison with the composite resin, celluloid crown. But they are not esthetic. To enhance the esthetics of the anterior stainless steel crown without reducing its superior retention, an open-face stainless steel crown has been suggested. Several authors have suggested cutting away the labial portion of the stainless steel crown and placing the composite resin in that area. By following this technique, the practioner can prepare a retentive, durable, and esthetic restoration for primary teeth which have suffered from extensive loss of teeth structure. In addition, the single missing primary anterior teeth can be successfully restored by soldering the stainless steel crown together. Open-face stainless steel crown is indicated in the areas of large interproximal lesions involving incisal edge, crown fracture with pulp exposure and congenital malformation of the teeth. By this technique, the practioner can restore primary anterior teeth successfully regardless of the amount of remaining tooth structure, bruxism habit and presence of attrition. In this case, rampant caries with extensive loss of tooth structure and single missing of primary anterior tooth hart been successfully treated with open-face stainless steel crown.

• 구강회복응용과학지
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• 제40권1호
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• pp.24-30
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• 2024

청소년기 외상으로 인한 상악 전치부의 복잡 치관 파절은 기능적, 심미적 문제를 야기할 수 있다. 치수 노출을 동반한 치관 파절은 남아있는 치질의 양에 따라 다양한 수복 방법을 고려할 수 있다. 직접 레진 수복은 가장 일차적으로 고려되는 전통적이고 효과적인 방법이나 시간이 지남에 따라 변색되고 깨질 가능성이 높다. 전장관 수복은 성장기의 치아 이동으로 변연 부조화에 의한 재수복 가능성이 높으며 광범위한 치관 파절 시 주로 시행하는 포스트 수복은 치근 천공 및 치근 파절의 위험성을 증가시킨다. 그러나 Endocrown은 치수강 공간으로부터 유지력을 얻을 수 있는 일체형 구조로 생체역학적 측면에서 효과적인 재건이 가능하고 기능과 심미성의 회복에 유리한 이점을 제공한다. 따라서 Endocrown은 청소년기 외상으로 인한 복잡 치관 파절의 수복 방법으로 고려할 수 있다.

• Restorative Dentistry and Endodontics
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• 제18권2호
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• pp.261-276
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• 1993

The purpose of this study was to evaluate for the cytotoxicity of glass-ionomer cement liners(GC liningcement, Ketac-bond, Vitrebond and Fuji lining LC) on the fibroblasts cultured from human pulp. The fibroblasts were cultured in DMEM-10% FBS medium. The measurement of pH, succinate dehydrogenase (SDH) activity test and $^{51}Chromium$ release test were performed. Viable cell count and $^{14}C$-leucine incorporation rate were evaluated following culture time of 2, 4 and 6 days. The results of this study were as follows : 1. The pH in all cements was to be neutralized as time elapsed, and Fuji lining LC was the lowest pH value among them. 2. SDH activity was more inhibited in GC lining cement and Vitrebond than Ketac-bond and Fuji lining LC with the setting process, and GC lining cement and Ketac-bond were reduced after 5 minute's setting and then elevated as time elapsed. 3. In SDH activity test following exposure time, the activity in Vitrebond, GC lining cement and Fuji lining LC was inhibited with increased exposure time, but it was fairly constant in Ketac-bond. 4. Overall the liquid component was more inhibited than the powder component of glass-ionomer cement in SDH activity test. 5. In $^{51}Cr$-release test, Fuji lining LC was the most released of all the cements tested and followed by : Vitrebond, Ketac-bond, GC lining cement. 6. In viable cell count, the number of cells increased as the culture day proceeded in Ketac-bond, but they decreased in GC lining cement. Fuji lining LC was only observed after 2 days culture and there was not observed the whole culture days in Vitrebond. 7. In $^{14}C$-leucine incorporation rate test, protein synthesis was decreased with the number of culture days in GC lining cement, Vitrebond and Fuji lining LC, but it was followed that of control in Ketacbond.

• The Korean Journal of Physiology and Pharmacology
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• 제18권1호
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• pp.25-32
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• 2014

Nitric oxide (NO) is recognized as a mediator and regulator of inflammatory responses. NO is produced by nitric oxide synthase (NOS), and NOS is abundantly expressed in the human dental pulp cells (HDPCs). NO produced by NOS can be cytotoxic at higher concentrations to HDPCs. However, the mechanism by which this cytotoxic pathway is activated in cells exposed to NO is not known. The purpose of this study was to elucidate the NO-induced cytotoxic mechanism in HDPCs. Sodium nitroprusside (SNP), a NO donor, reduced the viability of HDPCs in a dose- and time-dependent manner. We investigated the in vitro effects of nitric oxide on apoptosis of cultured HDPCs. Cells showed typical apoptotic morphology after exposure to SNP. Besides, the number of Annexin V positive cells was increased among the SNP-treated HDPCs. SNP enhanced the production of reactive oxygen species (ROS), and N-acetylcysteine (NAC) ameliorated the decrement of cell viability induced by SNP. However, a soluble guanylate cyclase inhibitor (ODQ) did not inhibited the decrement of cell viability induced by SNP. SNP increased cytochrome c release from the mitochondria to the cytosol and the ratio of Bax/Bcl-2 expression levels. Moreover, SNP-treated HDPCs elevated activities of caspase-3 and caspase-9. While pretreatment with inhibitors of caspase (z-VAD-fmk, z-DEVD-fmk) reversed the NO-induced apoptosis of HDPCs. From these results, it can be suggested that NO induces apoptosis of HDPCs through the mitochondria-dependent pathway mediated by ROS and Bcl-2 family, but not by the cyclic GMP pathway.

• 대한토목학회논문집
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• 제31권2A호
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• pp.105-113
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• 2011

본 연구는 보강섬유의 종류(마섬유, 펄프섬유, PVA섬유, 나이론섬유) 및 혼입률(0.0%, 0.1%, 0.2%, 0.3%)이 다공성 식생콘크리트의 역학적 특성과 내약품성에 미치는 효과를 평가하였다. 시험은 섬유의 종류 및 혼입률의 변화에 따른 다공성 식생콘크리트의 압축강도, 공극률, pH, 휨강도 및 내약품성 특성을 분석하기 위하여 수행하였다. 섬유의 종류 및 혼입률은 다공성 식생콘크리트의 압축강도, 공극률 및 내약품성에 영향을 미쳤다. 섬유의 혼입률이 증가할수록 압축강도, 휨강도 및 공극률은 증가하였다. 그렇지만 다공성 식생콘크리트의 pH 값과 내약품성은 섬유의 종류 및 혼입률의 변화에 큰 영향이 없었다.

• Toxicological Research
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• 제13권3호
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• pp.257-263
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• 1997

Pentachlorophenol(PCP) which ks widely used in wood preservation, pulp and paper mills, has led to a substantial envirortmental contamination. To get the reliable data for the effective health risk assessment with PCP, covalent binding potential of PCP to cellular macromolecules and glutathione(GSH) was investigated after intraperitoneal administration of $^{14}C-PCP$ to rats. PCP metabolites were able to bind covalently to serum albumin and hepatic protein in a dose- and time-dependent manner. Hepatic protein adducts of PCP metabolites were increased as a function of cytochrome P-450 activities, whereas, albumin adducts significantly decreased. Covalent binding of PCP metabolites with DNA or hemoglobin was not observed. GSH levels in liver tissue decreased over 12hrs, however, the level was recovered after 48hrs. Tetrachloro-1,4-benzoquinone (1,4-TCBQ), one of the most reactive PCP metabolites, conjugated with GSH very rapidly. Base on our results, we could conclude that PCP metabolized to reactive electrophilic metabolites by cytochrome P-450 isoenzymes and conjugated rapidly with neighboring protein or nonprotein sulfhydryl before reacting with DNA or hemoglobin. We propose that albumin adducts and mercapturic acids of PCP metabolites can be used good biomarker of recent PCP exposure.