변색 실활치에 대한 carbamide peroxide gel의 표백효과

박선아,김선호,황윤찬,오병주,윤창,박영준,정선와,황인남,오원만 大韓齒科保存學會 2002 Restorative Dentistry & Endodontics Vol.27 No.4

The bleaching of discolored nonvital teeth is conservative treatement that satisfy the cosmetic desire. The most common method for this treatement, walking bleaching, is using 30% hydrogen peroxide and sodium perborate. Many alternatives are suggested for preventing the external cervical root resorption that is the common complication of the nonvital teeth bleaching with 30% hydrogen peroxide. The same extent of oxidation reactions as that resulted by the bleaching with the application of 30% hydrogen peroxide and sodium perborate can also be acquired more safely by materials that contain 10% carbamide peroxide, used primarily for the bleaching of vital teeth. Therefore, this study was performed to evaluate the efficacy of 10% and 15% carbamide peroxide bleaching gel in nonvatal teeth bleaching. The internal bleaching of intentionally discolored teeth was performed in vitro with 10% carbamide peroxide (Group 1), 15% carbamide peroxide (Group 2), mixture of distilled water and sodium perborate (Group 3), and mixture of 30% hydrogen peroxide and sodium perborate (Group 4). The bleaching materials were refreshed following 3, 6, 9 and 12 days. To evaluate the bleaching effect, the color change of the crowns was measured at 1, 2, 3, 4, 7 and 15 days of bleaching using the colorimeter. The results were as follows : 1. L^* and ΔE^* values were increased with time in all bleaching agents(p<0.01). 2. There was no significant difference in L^* and ΔE^* value among bleaching agents. 3. Δ^* value higher than 3 was shown after 3 days of bleaching with 10% carbamide peroxide gel, 1 day with 15% carbamide peroxide gel, 4 days with mixture sodium perborate and distilled water and 4 days with mixture sodium perborate and 30% hydrogen peroxide, respectively. These results revealed that the use of 10% and 15% carbamide peroxide bleaching gel in non-vital teeth bleaching is as effective as mixture of distilled water and sodium perborate and mixture of 30% hydrogen peroxide and sodium perborate. Accordingly, carbamide peroxide could be used clinically to bleach discolored non-vital teeth.

타타늄의 열처리 조건에 따른 동전위 양극분극특성 및 표면 미세구조 변화

주동현,이용렬,정영화,양홍서,박상원,이도재,송호준,박영준 大韓齒科器材學會 2002 대한치과재료학회지 Vol.29 No.2

The corrosion resistance of metallic implants is essential for successful implant osseointegration. Moreover, the implant surface should have appropriate surface roughness for the attachment of the osteoblast and collagen fibrils. When titanium is exposed to air a thermodynamically very stable oxide film is formed at once. This oxide is very thin and yet it protects the metal from corrosion instantaneously. However, the oxide would not be ideal, and it would be supposed that the state of oxide film would be various by the different conditions when it is formed. The objective of this study was to evaluate the electrochemical properties and surface microstructural changes of titanium after passivation treatment or exposure to high heat (in vacuum or in air). ASTM grade 2 commercially pure titanium (Ti) disks of 10㎜ diameter were wet ground and polished with 240 and 600 grit SiC, and then ultrasonically cleaned with distilled water and ethanol. Cleansed as-received samples (As-R group) were passivated with 30% nitric acid solution at 50℃ for 15 minutes to make the Pas group. The Std-V samples were made by treating the Ti disks in vacuum quartz tube (10^-8 Torr) at 530℃ for 40 min for stress relieving, followed by annealing at 700℃ for 90 min, and then slow cooling to room temperature. The Std-A samples undergo identical procedure as the Std-V group except that it is done in air. For 530℃-V samples, Ti disks were heated at 530℃ for 40 minutes and slow cooled to room temperature. The 1000℃-V samples were produced by heating Std-V specimens again at 1000℃ for 2 hr, followed by cooling to room temperature. 530℃-A and 1000℃-A samples were also prepared. Potentiodynamic anodic polarization measurement, SEM, AFM and XRD analysis were performed to evaluate the effects of the various treatments. The difference in the mean values of E_corr between groups showed statistically significant difference (P<0.05), but that of I_corr did not show significance (P>0.05). When Ti surface was passivated there was a shift of corrosion potential (E_corr) in the noble direction and a lower corrosion current density (I_corr) value. Std-A samples showed most noble E_corr value among the tested groups. 530℃-V samples showed more noble E-corr than other tested groups except Std-A group. 1000℃-V samples showed more noble E-corr than those of Std-V sample. In the case of Std-, 530℃- and 1000℃-groups, -A sub-groups showed better corrosion resistant characteristics than -V sub-groups in regard to E-corr and I_corr values. In the SEM observations, the surfaces of the As-R samples showed only scratch line on smooth surface. In Pas samples, thick oxide layer covered the surface under high magnification observation. 530℃-A samples were covered by oxide granules, and Std-A samples had 25~50 nm-thick acicular oxides. The 1000℃-A samples were covered by coarse oxide crystals with a granule diameter of 0.1~0.6 μm having a gross appearance of milky white color, which was identified by XRD as a rutile. On the other hand, 1000℃-V samples showed an Widmansta¨tten structrue of which the orientation of the lattice is formed along crystallographic planes of the parent crystals. On the AFM observation, 530℃-A samples showed RMS roughness of 79.38 nm which is 5 times rougher than those of the As-R samples. Std-A sample had a roughness of 330.47 nm which is about 20-times rougher than that of the As-R sample. 1000℃-A samples were covered by coarse granular oxides and the roughness were about 0.56 μm. Vacuum sub-group samples showed a more smooth surface than air sub-group samples, and the oxide film was more dense. Due to variability of the surface treatment and heat treatment conditions, the process of the oxide formation seems to be affected thereby making the corrosion properties and surface micro-morphology different. However, more various electrochemical analysis together with surface analysis, and an investigation for the effects of those on the osteoblast cell adhesion and calcium phosphate apposition are needed for the improvement of the osseointegration rates of the titanium implants.

치과용 고무인상재의 영구변형 및 압축시 변형률

전창주,김준철,정석민,박영준 대한치과기재학회 2001 대한치과재료학회지 Vol.28 No.1

This study investigated the permanent deformation of dental rubber impression materials in order to evaluate their degree of recovery from displacement during removal through undercut area. We also investigated the stain in compression in order to evaluate the materials' flexibility during removal from the month, or during removal of the cast from the impression. Additional silicone, polyether, and polysulfied rubber impression materials were tested for their properties of permanent deformation and strain in compression according to the testing methods of the ADA specificaltion no. 19. 1.The permanent deformation values were as follows: polysulfide (2.25%), polyether (2.14%), and additional silicone (0.28∼1.21%, 2.38% for Perfect F). Examix, Express and Provil, which are additional silicone rubbers, showed lower permanent deformation values of 0.29%, 0.28% and 0.34%, respectively. Perfect F, although it is an additional silicone rubber, showed the highest permanent deformation value (2.38%) within the tested materials. 2.The strain in compression values were as follows: polysulfide (10.63%), additional silicone (2.88∼10.09%), and polyether (2.38%). The additional silicone rubber samples showed various values. Contrary to our expectations, it is also notable that Vinylate, which is used when taking an one-step impression, had higher stain in compression value (10.09%) than the light body impression materials even though it is classified as a heavy body material. Express (a.s.) had a low strain in compression (2.88%) which is similar to that (2.83%) of Impregum F (p.e.). In light body rubber materials, Permlastic had the highest value (p.s. 10.63%), followed by Perfect F (a.s. 7.38%), Correct VPS (a.s. 7.13%), Examix (a.s. 6.04%), Provil (a.s. 3.82%) and Express (a.s. 2.88%). Although the tested materials showed various values, all of them satisfied the requirements of A.D.A. Specification No. 19, which require that permanent deformation be less than 2.5%, and strain in compression be between 2∼20%.

한국인의 간과 콩팥조직 내 수은 함유량의 참고치

최병선,박영주,권일훈,홍연표,박정덕 한국환경독성학회 2002 환경독성보건학회지 Vol.17 No.2

This study was conducted to investigate the reference value of mercury (Hg) in liver and kidney of Korean population. The mercury concentration in 244 'sudden and unexpected death' autopsies (male: 180, female: 64) aged from 0 to87 years was analyzed. The concentration of mercury was measured by atomic absorption spec(Perkin -Elmer Model 5100) with mercury/hydride generating system (FIAS 400). The contents of mercury in liver and kidney fitted well the log-normal distribution rather than normal distribution. Geometric mean concentration of mercury in liver and kidney was 0.115 ㎍/g wet weight and 0.149 μg/g wet weight, respectively. Geometric mean concentration of mercury in female was higher than in male (p<0.01). The mercury content in liver and kidney increased with age up to the forties and slightly decreased there-after, The regression model of mercury deposit in liver and kidney by age was predicted as the following equation : Log KHg=-1.0576+0.0045·Age -0.0001·Age²+0.0873·Sex, Log KHg=-1.0576+0.0152·Age-0.0002·Age²+0.1935·Sex. The liver burden of mercury was estimated to be 158.3~161.3μg in male and 163.0-166.9 ㎍ in female. The kidney burden of mercury was estimated to be 42.0~42.9 ㎍ in male and 55.5 ∼57.1 μg in female.

흡입물질의 위생학적 연구 : 본드 흡입이 흰쥐의 폐 및 기타 장기의 효소 활성에 미치는 영향 The Effect of Bond Inhalation on the Enzyme Activity of Lung and Other Organs in Rat

윤수홍,박은주,이주영,서혜령 효성여자대학교 부설 한국환경위생연구소 1991 환경위생연구 Vol.1 No.1

Toluene, alcohol및 vinylester류 등을 함유하고 있는 bond를 이용하여 휘발성 물질이 생체에미치는 영향을 관찰하기 위하여 rat에 일정 농도의 bond를 일정 시간 흡입시킨 뒤 각 조직에대하여 효소의 생화학적 시험과 celluloseacetate electrophoresis를 실시하여 다음과 같은 결과를얻었다. 1. Bond 흡입은 시간이 증가함에 따라 혈청, 심장, 신장, 근육, 뇌의 ChE 활성을 억제하였으며특히 폐와 간장의 ChE활성에 가장 큰 영향을 나타내었다. 2. Bond 흡입에 의해 혈청 및 각 조직 중에서 LDH활성이 증가되었으며 특히 폐와 심장,근육에서 그 영향이 현저히 나타났다. 3. Celluloseacetate electrophoresis를 통한 각 조직의 LDH isozyme pattern에는 차이가 나타났으며 bond 흡입에 의해 band의 소멸과 선명도의 감소가 일어 났는데 특히 폐에 대한 독성이가장 현저했으며 근육에 대한 독성도 큰 것으로 나타났다. Acute poisoning with organic solvents and other volatile compou-nds now usually follows deliberate inhalation(volatile substance abuse) or inges-tion of these compounds. The effect of bond inhalation was analyzed for serum, liver, lung, brain,heart, kidney and muscle. And the observations are revealed on rat cholinesterase activity, lactatedeh-ydrogenase activity and electrophoretic pattern of lactatedehydrogenase isozyme. The results are as follows ; 1. The rat cholinesterase activity on serum, heart, muscle, kidney and brain showthe decrease by increasing of inhalation time of bond, in particular the lungand liver cholinesterase activity was greatly affected. 2. Bond inhalation brough out the lactatedehydrogenase activity increased ofthe serum and the tissues and had an important effect especially in both thelung and muscle lactatedehydrogenase activities. 3. Each tissue was found to have a characteristic distribution of lactatedehydro-genase isozymes on celluloseacetate elelctrophoresis and the development ofinhalation time is shown the disappearence and diffusion of band.

The Identification of Aucklandiae Radix, Inulae Radix, Vladimiriae Radix and Aristolochiae Radix, Using Macroscopic, Microscopic and Physicochemical Methods

Yoon, Jee-Hyun,Park, Ha-Yeong,Kim, Tae-Ju,Lee, Seung-Ho,Kim, Jung-Hoon,Lee, Guem-San,Kim, Hong-Jun,Ju, Young-Sung The Society of Korean Medicine 2014 대한한의학회지 Vol.35 No.4

Objectives: This study aimed for establishing the discriminative criteria for Aucklandiae Radix, Inulae Radix, Vladimiriae Radix and Aristolochiae Radix, which can be confused as 'Mokhyang', because of similar appearances and synonyms. Methods: Morphological characteristics of dried herbal medicines were compared by macroscopic observation. To examine microscopic features of 'Mokhyang', paraffin embedding and the staining by using Ju's method were conducted. Physicochemical experiments were performed using HPLC analysis and antioxidant assay. Results: The types of stem, phyllotaxy and leaf shape were chosen as macroscopic criteria and the size, oil spots, color and root top as well as phloem and central cylinder were compared using microscopic features. The HPLC results showed different amounts of costunolide and dehydrocostuslactone among Aucklandiae Radix, Inulae Radix and Vladimiriae Radix. However, Aristolochiae Radix only contained aristolochic acid. The antioxidant assays also showed that Vladimiriae Radix exhibited strongest antioxidant activity followed by Aucklandiae Radix, Inulae Radix and Aristolochiae Radix. Conclusions: These results demonstrate that macroscopic, microscopic and physicochemical methods would be useful tools for the discrimination of 4 kinds of 'Mokhyang'.

The Identification of Aucklandiae Radix, Inulae Radix, Vladimiriae Radix and Aristolochiae Radix, Using Macroscopic, Microscopic and Physicochemical Methods

Jee-Hyun Yoon,Ha-Yeong Park,Tae-Ju Kim,Seung-Ho Lee,Jung-Hoon Kim,Guem-San Lee,Hong-Jun Kim,Young-Sung Ju 대한한의학회 2014 대한한의학회지 Vol.35 No.4

播種期, 苗令 및 土壤水分不足이 黃色種 담배의 生育 및 收量에 미치는 影響

盧載榮,申周植,朴然圭,孫錫龍 충북대학교 엽연초연구소 1984 煙草硏究 Vol.11 No.-

This experiment was conducted to study the influence of environment cultural method and their interaction on the growth and yield components of flue-cured tobacco. Applied variety was NC 2326, and was treated by sowing time(Mar. 11, Mar. 21 and Mar.31), seedling age (40,50 and 60 day) and soil moisture stress period (20 days from 10, 20 and 30 days after setting). The results are summarized as follows. 1.During growing period, stem height, length and width of the largest leaf and total leaves were affected remarkably by the treatments. 2.Soil moisture stress period affected more the characters of tobacco plants than other factors. 3.The tobacco plant treated by early stage soil moisture stress (period from 10 to 30 days after setting) made the early growth very poor, and that tobacco plant showed poor growth until 45 to 50 days after setting. 4.Early sowing, 40 day seedling and early stage soil moisture stress made the plant type sylindrical, and late sowing and 50 to 60 day seedling made the plant type cone shape. 5.Number of total leaves and harvested leaves, leaf area per plant percentage of dry matter of leaf and specific leaf weight decreased by the treatment of soil moisture stress during early and middle part of maximum growth stage. 6.There were little differences of yield among the treatment of different sowing time and seedling age. Early sowing increased the thickness of leaf and weight per unit leaf area, and decreased number of total leaves and specific leaf weight. Number of total and harvested leaves and specific leaf weight of cured leaves were high in the plot of 60-day seedling 40-day seedling showed heavy weight of unit leaf area and low specific leaf weight of cured leaves. 7.From the point of view of interaction between sowing time and seedling age, early sowing (Mar. 11) with 60-day seedling, middle sowing (Mar. 21) with 50-day seedling and late sowing (Mar. 31) with 40-day seedling are recommended. 8.Rapid growth of early growing stage was shown in the plot of adequate soil moisture and late sowing (Mar. 31) with 50-day to 60-day seedling. 9.From the point of standard quality of cured leaves, sowing time can be shifted until late March. And to fix the sowing time, It should be considered that the maximum growth stage and the harvesting time of cutter and leaf would not match with severe drought of May and rainy season of early summer respectively.

VDT작업별 정신사회적 스트레스와 근골격계 장애에 관한 연구

백남종,강종두,주영수,배인근,권호장,박종만,조수헌,김돈규,김재용,최홍렬 大韓産業醫學會 1998 대한직업환경의학회지 Vol.10 No.4

It has been hypothesized that jobs that have both high psychological demands and low decision latitude("job strain") can lead to musculoskeletal disorder. The objective of this study was to test whether job strain was correlated with the presence of work-related musculoskeletal disorder, especially myofascial pain syndrome(MPS). Information on demographic factors, confounders such as household load and taking care of children or not, and scores for decision latitude, job demand, and social support was obtained by self-administered questionnaire, which had been developed in Korean language, by adopting NIOSH instrument and Extended Karasek Model(16 items). All subjects were also examined by rehabilitation medicine specialists for musculoskeletal disorders. Subjects(n=370) could be categorized into 4 groups, these were, housewives(n=89), shipyard CAD workers(n=89), general female workers(n=79; nurses, insurance counselors, public officials, clerks, etc), and telephone directory assistance operators(n=113). Results from univariate analyses indicated that all demographic factors, all confounders, scores for decision latitude and social support were not associated with the risk of musculoskeletal disorder. However, score for job demand was higher in musculoskeletal disorder cases than others. In subgroup analysis, this association was convinced again, in telephone directory assistance operators. Job strain model showed that the group of telephone directory assistance operators was high-stain group, and OR of musculo skeletal disorder was 2.446(95% C. I. : 1.174, 5.096), when comparing this with the low strain group. In conclusion, job strain is a risk factor for work-related musculoskeletal disorder.

다발성 골수종에서 저용량 thalidomide, cyclophosphamide, dexamethasone (TCD) 요법의 효과

류충헌,정재현,고정해,장제혁,박영진,최규남,박봉수,이상민,주영돈 인제대학교 2008 仁濟醫學 Vol.29 No.-

Background and Objectives : The immunomodulatory drug thalidomide can inhibit angiogenesis and induce apoptosis in experimental models. It can also induce marked and durable response in newly diagnosed myeloma patients. Thalidomide has been used at doses ranging from 200 to 800 mg with significant toxicity. No data are available on the impact of low-dose thalidomide, cyclophosphamide and dexamethasone as initial therapy for myeloma patients. Design and Methods : To address this issue, newly diagnosed myeloma patients were treated with 50 mg/day thalidomide continuously and cyclophosphamide 150 mg/m², days 1-4 and dexamethasone 20 mg/m², days 1-5 and day 15-19, every month. Between October 2005 and October 2006, 14 patients (median age 54.5 years) were treated with low-dose thalidomide, cyclophosphamide and dexamethasone. Results : After a minimum of two cycles of treatment, 5 patients (55.5%) showed a partial remission. After four cycles of treatment, 10 patients (83.3%) showed a partial remission (n=6) and complete remission (n=4). After a median follow-up of 15.4 months, 1 year overall survival rate was 82.0%. Thalidomide was well tolerated without serious toxic effects. Conclusions : The combination of low-dose thalidomide, cyclophosphamide and dexamethasone demonstrates favorable response rate and 1 year overall survival rate in newly diagnosed myeloma. Severe toxicities were not seen with this combination.