• Title, Summary, Keyword: CASTS

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Accuracy of casts produced from conventional and digital workflows: A qualitative and quantitative analyses

  • Abduo, Jaafar
    • The Journal of Advanced Prosthodontics
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    • v.11 no.2
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    • pp.138-146
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    • 2019
  • PURPOSE. Comparing the accuracy of casts produced from digital workflow to that of casts produced from conventional techniques. MATERIALS AND METHODS. Whole arch alginate (ALG) and polyvinyl siloxane (PVS) impressions were taken with stock trays and custom trays, respectively. The ALG impressions were poured with type III dental stone, while the PVS impressions were poured with type IV dental stone. For the digital workflow, IOS impressions were taken and physical casts were produced by 3D printing. In addition, 3D printed casts were produced from images obtained from a laboratory scanner (LS). For each technique, a total of 10 casts were produced. The accuracies of the whole arch and separated teeth were virtually quantified. RESULTS. Whole arch cast accuracy was more superior for PVS followed by LS, ALG, and IOS. The PVS and ALG groups were inferior in the areas more susceptible to impression material distortion, such as fossae and undercut regions. The LS casts appeared to have generalized errors of minor magnitude influencing primarily the posterior teeth. The IOS casts were considerably more affected at the posterior region. On the contrary, the IOS and LS casts were more superior for single tooth accuracy followed by PVS and ALG. CONCLUSION. For whole arch accuracy, casts produced from IOS were inferior to those produced from PVS and ALG. The inferior outcome of IOS appears to be related to the span of scanning. For single tooth accuracy, IOS showed superior accuracy compared to conventional impressions.

Comparisons of Soil Properties between Earthworm Casts and Top Soil of Red Pine Forests in a Limestone Area (石灰岩地域 소나무림에서 지렁이 Casts 와 上層土 性質의 比較)

  • Mun, Hyeong-Tae;Joon-Ho Kim
    • The Korean Journal of Ecology
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    • v.14 no.1
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    • pp.113-117
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    • 1991
  • Comparisons of the physico-chemical properties of earthworm(Lumbricus terrestris) soil casts and top soil of red pine forests in a limestone area were carried out. The casts production durign August and September in 1990 amounted to 6∼7t/ha. The particle of top soil and casts ranged 40∼50% and 10∼20% for sand , 25∼30% and 30∼35% for silt, and 20∼25% and 55∼65% clay, respectively. Significant difference in pH value was not observed between casts and top soil. The casts had 1.4times of organic matter, 1.5times of N, 1.8times of available P, 2times of exchangeable K, 1.3times of exchangeable Ca, and 1.6times of exchangeable Mg than the top 10cm of soil did. Earthworms have altered the soil texture and increased nutrient availability through production of the soil casts in this limestone area.

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The Effects of Earth Worm Casts as a Plant Growth Media on the Growth of Orchardgrass Seedlings (Plant Growth Media로써 지렁이 분립이 Orchardgrass 생육에 미치는 영향)

  • Lee, Pil-Won;Lee, Ju-Sam
    • Korean Journal of Organic Agriculture
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    • v.7 no.2
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    • pp.179-188
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    • 1999
  • The effects of earthworm casts as a plant growth media on the growth of orchardgrass seedlings and the changes of physico-chemical properties in worm casts mixture soils were investigated during the growth period of 1998. Worm casts were mixtured with vermiculite, perlite and peat moss, and mixture ratios of worm casts with commercial recommended soil were 100:0(control), 75:25, 50:50, 25:75, and 0:100, respectively. The results were obtained as follows; 1. Plant length(PL) was increased in higher mixture ratios of worm casts and peat moss than those of other mixture ratios of commercial recommended soils. 2. Number of tillers(NT) were significantly increased in mixture ratios of worm casts and peat moss(50:50) and 100% of vermiculite. 3. Root length(RL) was significantly differences between mixture ratios at the worm casts, and the highest value was obtained at all mixture ratios of worm casts and perlite. 4. Dry weight of leaf(LW) was not significantly differences at mixture ratios of 50:50 in all treatments. Especially, between the mixture ratios of worm casts with peatmoss(25:75) and peat moss(75:25) were not significantly differences in dry weight of leaf(LW). The highest value of dry weight of leaf(LW) was obtained at mixture ratios of peat moss and worm casts. 5. Dry weight of tillers(SW) was not significantly differences at mixture ratios of 50:50 in all treatments, and peat moss(75:25) and vermiculite(75:25), respectively. 6. biological yield(BY) at all treatments were increased by yield components of dry weight of tillers(SW), dry weight of root(RW) and length of root(RL). 7. The biological yield of orchardgrass seedlings was greatly increased with mixture ratios of worm casts and peat moss over the 50%.

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A study on recycling of cast as adsorbent (흡착제로서 분변토 재활용에 관한 연구)

  • 손희정;전성균;하상안
    • Journal of environmental and Sanitary engineering
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    • v.15 no.3
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    • pp.44-49
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    • 2000
  • The purpose of this research is to evaluate the adsorption capacity of casts for heavy metals. The casts were excreted by earthworm, Lumbricus rubellus, after having eaten the paper sludge. Various batch experiments on adsorption were performed to compare cast and activated carbon. The pH increase in solution due to extractives from cast was 1.3 and the cation exchange capacity which implies adsorption capacity for solubles is greater on activated carbon than on cast. According to the results of batch experiment, the removal rates of Pb, Cu, Cr, Zn using the activated carbon and casts as adsorbent were 98%, 93%, 94%, 89%, 82% and 95%, 90%, 88%,80%, 66%, respectivity, and this removal were achived less than 90 minutes. It can be said that casts is so good adsorbent as activated carbon is, although adsorption carbon was found to be some large than those of casts through Freundlich isotherm applied for adsorption of soluble. As a result on the experiment of isothermic adsorption from the mixed component solution in the batch, the order of preferable elements in heavy metal adsorption was found to be Pb>Cd>Cu>Cr>Zn on activated carbon, respectively.

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A Study on Castability and Roughness of the Casts Using Non-precious Alloys (비귀금속 합금을 이용한 주조체의 주조성과 Roughness에 관한 연구)

  • Kim, Jang-Ju
    • The Journal of Korean Academy of Dental Technology
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    • v.20 no.1
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    • pp.5-11
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    • 1998
  • The purpose of this study is to evaluate the castability and surface roughness of the casts using Non-percious alloys. For samples of 25 wax patterns, it is made from eight layers of sheet wax, arranged in the escalating layers. After fabricated wax patterns, using 5 kinds of Ni-Cr alloys is casted, and the casts are sandblasted. To castability, magnifier is used and values of surface roughness of the casts is measured with profilometer(tracing length 1.75mm, cutoff value 0.25mm) The results are as follows : 1. The castanbility of alloys, in case of C alloys, showed with $8.0{\pm}0.0000$, and in case of CS alloys and N alloys showed equal with $7.8{\pm}0.4472$, respectively. T alloys and V alloys showed equal with $7.2{\pm}0.4472$, respectively. 2. The values of surface roughness of the casts are decreased more T alloys than in case of order alloys, and in order, increased in case of CS alloys, C alloys, V alloys, N alloys, respectively.

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Recycling of Casts as an Adsorbent for Phosphorous Removal (인제거를 위한 흡착제로써 분변토 재활용)

  • 손희정;김은호;이용희
    • Journal of environmental and Sanitary engineering
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    • v.13 no.2
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    • pp.76-81
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    • 1998
  • The technology of removing phosphorous, considered as one of the most important control nutrients causing eutrophication in various water bodies, have been investigated by many researchers. In this study, casts which can be obtained from the vermicomposting of mixing sewage sludge and cow manure, were used as an adsorbent, and their effects of several physical/chemical factors on the efficiencies of phosphorous adsorption were examined by batch tests. Generally, it could be showed that the efficiencies of phosphorous adsorption were very influenced by cast dosage, temperature and agitation speed. If we reflected the adsorption capacity(k) and adsorption intensity(1/n) of Freundlich isotherm, we couldn't consider casts as a good adsorbent for removing phosphorous. But, because casts were relatively excellent in cation exchange, in point of waste recycling, we could know that they were capable of removing phosphorous. The SEM observation revealed that the evident variations were hardly seen, but particle sizes of cast were relatively bigger and showed forms of smaller plate than before.

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The Effects of the Mineral Oil on Skin under Casts for Relief of Skin Dryness and Pruritus (석고붕대 속 피부에의 미네랄오일 도포가 피부건조 및 소양감 완화에 미치는 효과)

  • Lee Byung-Sook;Baek Kyung-Hee
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.10 no.2
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    • pp.187-197
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    • 2003
  • Purpose: This experimental study was to verify the effects of the mineral oil on skin under casts for relief of skin dryness and pruritus. Method: Participants in the study were inpatients at C university hospital in D city who had long leg casts. The mineral oil was applied to the skin under the casts in the experimental group of 18 patients and was not applied to the control group, also 18 patients. During the experimentation, the participants in the experimental group were informed about how to apply the mineral oil and 1 week later were responsible for applying the oil themselves. The oil was applied three times a day. Data collection was done from July 28, 2002 to September 28, 2002. The analyses were carried using frequencies, percentages, $x^2$-test, t-test, and repeated measures ANOVA with the SPSS WIN 10.0 program. Results: Hypothesis 1, 'The experimental group using the mineral oil application showed remarkably less dryness in the skin compared to the control group' was accepted (F=16.39, p=0.000). Hypothesis 2, 'The experimental group using the mineral, oil application showed remarkably less pruritus compared to the control group' was accepted (F=34.01, p=0.000). Conclusion: These results demonstrate that mineral oil application to skin under casts was effective in treating skin dryness and pruritus. Accordingly, it is concluded that mineral oil application to skin under casts can be an effective nurse intervention to treat skin dryness and pruritus.

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EFFECT ON IMMERSI0N DISINFECTION OF HYDROPHIILIC RUBBER IMPRESSI0N MATERIAL ON DIMENSIONAL STABILITY AND SURFACE HARDNESS OF IMPROVED STONE CAST (친수성 고무인상재의 침적 소독이 경석모형의 크기의 안정성과 표면경도에 미치는 영향)

  • Nam, Mee-Hyun;Kang, Woo-Jin;Chung, Moon-Kyu
    • The Journal of Korean Academy of Prosthodontics
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    • v.33 no.3
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    • pp.569-583
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    • 1995
  • Disinfection of dental impressions are necessary due to contamination with patient’s saliva and blood, which is a potential for cross-infection. The purpose of this study was to evaluate the effects of disinfection of four hydrophilic rubber impression materials with three disinfecting solutions, on the dimensional stability and surface hardness of improved stone casts. Three hydrophilic vinyl polysiloxane impression materials(Express, Reprosil, Exafine) and one polyether impression material(Impregum-F) were mixed according to the manufacturer’s directions and impressions were made on a ADA specification No. 19 stainless-steeldie. On removal of the impressions, each impression was immersed in one of the disinfectants(Banicide, Potadine, Clorox) for 10 minutes. After disinfection, type IV improved stone. casts were poured. On this cast, the linear dimension and surface hardness were measuredusing a Measurescope(Nikon, Japan) and a Barcol hardness tester(Barber, Colman Co U. S. A). The results were as follows : 1. The improved stone casts from disinfected Reprosil and Impregum-F impression material did not show dimensional changes(P>0.01). Those from disinfected Express and Exafine impression material showed dimensional changes(P<0.01). The amount of shrinkage was not clinically significant. 2. The improved stone casts from disinfected Express impression material did not exhibit changes in surface hardness(P>0.01), but those from disinfected Reprosil, Exafine, Imp regnum-F impression material showed changes in surface hardness(P<0.01). 3. The dimensinal stability and surface hardness of the improved stone casts were satisfactory using Banicide on Express, all disinfectants used in this study on Reprosil, Potadin and Clorox on Exafine, Banicide and Clorox on Impregum-F. According to these results, immersion disinfection of hydrophilic rubber impression mate rials did not adversely affect the resultant casts. Nevertheless compatibility tests of impression materials and disinfectants should be done when disinfecting impressions.

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Color cast detection based on color by correlation and color constancy algorithm using kernel density estimation (색 상관 관계 기반의 색조 검출 및 핵밀도 추정을 이용한 색 항상성 알고리즘)

  • Jung, Jun-Woo;Kim, Gyeong-Hwan
    • Journal of Korea Multimedia Society
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    • v.13 no.4
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    • pp.535-546
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    • 2010
  • Digital images have undesired color casts due to various illumination conditions and intrinsic characteristics of cameras. Since the color casts in the images deteriorate performance of color representations, color correction is required for further analysis of images. In this paper, an algorithm for detection and removal of color casts is presented. The proposed algorithm consists of four steps: retrieving similar image using color by correlation, extraction of near neutral color regions, kernel density estimation, and removal of color casts. Ambiguities in near neutral color regions are excluded based on kernel density estimation by the color by correlation algorithm. The method determines whether there are color casts by chromaticity distributions in near neutral color regions, and removes color casts for color constancy. Experimental results suggest that the proposed method outperforms the gray world algorithm and the color by correlation algorithm.

Fatal plastic bronchitis with eosinophilic casts in a previously healthy child (건강하였던 소아에서 발생한 치명적인 호산구성 증식성 기관지염)

  • Cho, Young Kuk;Oh, Soo Min;Choi, Woo-Yeon;Song, Eun Song;Han, Dong-Kyun;Kim, Young-Ok;Ma, Jae Sook
    • Korean Journal of Pediatrics
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    • v.52 no.9
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    • pp.1048-1052
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    • 2009
  • Plastic bronchitis is a rare disease characterized by the recurrent formation of branching mucoid bronchial casts that are large and more cohesive than those that occur in ordinary mucus plugging. Casts may vary in size and can be spontaneously expectorated, but some require bronchoscopy for removal. Plastic bronchitis can therefore present as an acute life-threatening emergency if obstruction of the major airways occurs. Three of 22 reported patients with eosinophilic casts were fatal, with death due to central airway obstruction. Here, we report a child with no history of atopy, allergy, or congenital heart disease who was diagnosed with plastic bronchitis with eosinophilic casts. Although he was administered intravenous (iv) antibiotics; iv corticosteroids; and a vigorous pulmonary toilet regimen, including chest physiotherapy and routine bronchoscopic removal of casts, he had brain death secondary to hypoxic brain damage. Plastic bronchitis can be fatal when casts obstruct the major airways, as in the present case. Clinicians should intervene early if a patient exhibits signs and symptoms consistent with plastic bronchitis.