• Restorative Dentistry and Endodontics
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• v.9 no.1
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• pp.7-14
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• 1983

The purpose of this study was to investigate pulpal responses to tricalcium phosphate and durapatite which recently introduced as a bone substitute. Tricalcium phosphate and durapatite were placed on the amputated pulp tissue in the dog's teeth. Animals were sacrificed after 1, 2, 3 and 4 weeks and specimens were decalcified, embedding, sectioned and stained routinly. Microscopic examination reveals as follows; 1. Tricalcium phosphate: Severe inflammatory change was seen in the all cases and calcified masses were seen at 2 weeks. Calcified masses were enlarged according to the time elapsed. 2. Durapatite: Severe inflammatory change and pus cavities were found at 1 week. There was no evidence of healthy cell component in the remaining pulp tissue and degenerative change was obvious at 2, 3 and 4 weeks. 3. Dentin bridge was not formed in the both cases. In the case of tricalcium phosphate osteoblasts were observed unevenly around the calcified masses which were composed of hematophilic substance in central portion and eosinophilic substance in peripheral region of the masses.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.3
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• pp.96-104
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• 1999

Anatomical and chemical properties of three mulberry species (Morus spp) were analyzed as an alternative row material for the paper mulberry (Broussonetia kazinoki) . The pulping and papermaing characteristics of bast fiber and whole stalks by three different pulping processes, conventional alkali, alkali-hydrogen peroxide, and sulfomethylated, for the Hanji were investigated. The fiber dimension of M.bombycis was the biggest of the species. The fiber length of upper part and the fiber width and cell wall thickness of lower part were bigger than the others. The extractives and ash contents of bast fiber were higher than those of whole stalk , and holocellulose and lignin contents of whole stalk were higher than those of bast fiber. The pulp yields of M.alba bast fiber, M.bombycis whole stalk, and sufomethylated pulping were higher than the others.

• Korean Journal of Microbiology
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• v.14 no.1
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• pp.1-7
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• 1976

Effect of some nutrients on the growth of 3 yeast strains in the pulp mill waste liquor was determined during an attempt to lower the BOD content of the waste liquor and to produce the fodder yeast. The strains applied were Debaryomyces castelli Capriotti, D.phoffi Capriotti, and Cryptococcus luteolus (Saito)Skinner. The necessity of the addition of 0.2% ${NH_4}2SO_4$ 0.5% yeast extract, 0.2% $NH_2SO_4$, and 0.1% $MgSO_4$.$7H_2$O for the best growth of all three strains in the waste liquor was ascertained as a result. After 3-day treatment of the yeast cells on the waste liquor, the BOD content was lowered by about 60-70%. Harvested yeast cells contained ca. 75% water with 1.5-3% lipid, 40-46% protein, 50% carbohydrate and 3-5% ash on the dry weight basis, indicating the possibility of being utilized as the fodder yeast.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.1
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• pp.151-160
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• 2000

The effect of concentration as factor in cytotoxicity, protein synthesis and alkaline phosphatase activity was compared for pulpotomy medicaments (formaldehyde, formocresol, paraformaldehyde, ferric sulfate) Human pulp fibroblasts were exposed to a range of concentrations(0.01, 0.05, 0.10, 0.25, 0.50, $1.00{\mu}l/ml$) of each agents, for period of 24hrs. The cell activities were evaluated by MTT assay, protein assay and alkaline phosphatase activity examination. The results as follows : 1. After 24hrs culture, pulp fibroblasts adding formaldehyde, formocresol and paraformaldehyde were suppressed cell activities with concentration increasing, but, no depression of cell activities by ferric sulfate. No significant difference was in formaldehyde, formocresol and paraformaldehyde. 2. Protein synthesis by pulpotomy agents were not significant difference in pulp fibroblasts but protein synthesis were a little decreased by paraformaldehyde. 3. Alkaline phosphatase activity was a little decreased by pulpotomy medicaments.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.1
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• pp.7-12
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• 2010

Morphological characteristics of hemp fiber were investigated using a light microscope in order to provide fundamental data for the use of hemp as a papermaking law material. Phloem of hemp is composed of cortical parenchyma cells and bast fiber with thick walls while xylem is composed of vessel, wood fiber and ray parenchyma cells. Also there are solitary pore and radial pore multiple which exist in diffuse porous pattern. Ray cells consist of uniseriate rays and thin walled ray parenchyma cells. Wood fibers are composed of three types: a large diameter fiber with longer length; a large diameter fiber with shorter length; a small diameter fiber with medium length. Vessel elements are composed of: a medium length one; a longer length one; the one whose both end walls have ligules or tails. Parenchyma cells in xylem and pit parenchyma cells have completely different size and shape. For bast fiber, the average length is about 4.4 mm and the width is about $30.5\;{\mu}m$; for vessel element, $600.0\;{\mu}m$ in length and $493.6\;{\mu}m$ in width; for wood fiber, $1000\;{\mu}m$ and $38.9\;{\mu}m$; for parenchyma cell, $50\;{\mu}m$ and $26.4\;{\mu}m$.

• Restorative Dentistry and Endodontics
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• v.15 no.2
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• pp.58-76
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• 1990

This study was designed to elucidate the distribution of the immunoglobulins in the experimentally induced rat periapical lesions. The pulp exposure was performed in 80 molars from 40 rats and the animals were sacrificed at 15, 30, 60 and 90 days after the operation and examined and radiographed. Of the 80 samples, 56 samples were routinely sectioned ($4-6{\mu}$ in thickness) and stained with Hematoxylin-Eosin for the light microscopic examination and 50 samples were stained with toluidin blue for mast cells and 50 samples were stained using the Avidin-Biotin horseradish peroxidase for detecting the presence of Ig A, Ig E, Ig M and Ig G containing cells. The following results were obtained : 1. The periapical lesions could be observed in all of 80 teeth by radiogragh (100%) and the periapical lesions were detected in 50 samples of 51 samples by light microscopy (98%). The size of lesions increased with time lapse both by radiograph and by light microscopy(p<0.05). 2. Of the 50 samples, 19 samples were diagnosed as periapical abscesses, 18 as periapical granulomas, 10 as fibrous scar tissues and 3 cysts. 3. After pulp exposure, periapical granulomas were developed mostly in the 15 day group, with time lapse periapical abscesses and fibrous scar tissues increased. 4. In the 50 periapical lesions, the numbers of Ig G containing cell (57.2%) were prominent and the percentage of Ig A, Ig E and Ig M containing cells were 16.4%, 14.7% and 11.8% respectively. The numbers of all classes of immunoglobulin containing cell were highest in the periapical granulomas and lowest in the cysts(p<0.05). 5. The number of the mast cell and immunoglobulin containing cells decreased generally with time lapse after the pulp exposure and Ig A, Ig E, Ig M and Ig G containing cells and mast cells had the high correlation one another(>0.6).

• Restorative Dentistry and Endodontics
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• v.41 no.4
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• pp.283-295
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• 2016

Objectives: In this study, we characterized human dental pulp cells (HDPCs) obtained by different culture methods to establish the most suitable methodology for dental tissue engineering and regenerative endodontic applications. Materials and Methods: HDPCs were isolated by the outgrowth method (HDPCs-OG), the enzymatic digestion method (collagenase/dispase/trypsin, HDPCs-ED), or the combination of both methods (HDPCs-Combined). The expression of mesenchymal stem cell markers (CD105, CD90, and CD73) was investigated. In vitro differentiation capacities of HDPCs into adipogenic, osteogenic, and chondrogenic lineages were compared. Differentiation markers were analyzed by quantitative reverse-transcription polymerase chain reaction (RT-PCR) and western blotting. Results: Our data indicated that whole HDPCs-ED, HPDCs-OG, and HDPCs-Combined could be differentiated into adipogenic, chrondrogenic, and osteogenic cell types. However, we found that the methods for isolating and culturing HDPCs influence the differentiation capacities of cells. HDPCs-OG and HDPCs-ED were preferably differentiated into adipogenic and osteogenic cells, respectively. Differentiation markers shown by RT-PCR and western blotting analysis were mostly upregulated in the treated groups compared with the control groups. Conclusions: Our findings confirmed that cell populations formed by two different culture methods and the combined culture method exhibited different properties. The results of this study could provide an insight into regenerative endodontic treatment using HDPCs.

• Journal of Oral Medicine and Pain
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• v.9 no.1
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• pp.127-138
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• 1984

The author had tried to identify the sex from single tooth by detecting F-body of Y-chromosome in the nucleus of the dental pulp cells of 70 persons aged from 4 to 61 years under a fluorescent miscroscope. The results were as follows : 1. In the cell nuclei of male and female dental pulp at refrigeratory, the rate of F-body appearancd ranged 42-86%(average 61.06%) in male, while it was 0-6%(average 1.86%) in female, indicationg that male could be distinctly differentiated from female by F-body. 2. With male and female dental pulp puterfide by leaving in at room temperature, the rate of F-body appearance ranged 35-58%(average 48.20%) in male, 1-3%(average1.70%) in female, indicating that it was possible to distinguish male and female by F-body. 3. Even in heat-treated male teeth at $100^{\circ}C$,10 mins, the rate of F-body appearace proved to be 32-56%(averaged 42.50%), also indicating the possibility of identifying male. 4. When detecting of F-body in process of time, the rate of F-body appearance did not show major charges. 5. It was reaffirmed that F-body detection method was a positive determination method of male.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.6
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• pp.30-35
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• 2013

To conserve wood resources for papermaking, chemical compositions of the hemp (Cannabis sativa L.) bast fiber cultivated in Korea such as holocellulose, ${\alpha}$-cellulose, lignin, alcohol-benzene extractives, hot and cold water extractives, and ash contents were investigated to manufacture the specialty packaging paper effectively. Significantly very low klason lignin content of 3.3% was accomplished by removing of the outer shell of bark. Laboratory soda pulping method which is very useful for the nonwood fiber was adapted, and it was found that there was no significant difference in both kappa number and H-factor between 25% and 30% NaOH charge. Hemp pulp cooked with the laboratory digester in 25% NaOH at $170^{\circ}C$ were mixed together with the wood pulp(NBKP:LBKP=1:1) in order to find the optimum mixture ratio which exhibited acceptable paper strength properties such as tensile index, burst index, and tear strength. When 10% of hemp soda pulps was mixed with 90% of wood pulps comprised of SwBKP and HwBKP (1:1), all physical strength increased significantly. The physical strength decreased as the amount of hemp pulp increased because the cell wall of bast fiber is very thick which causes low conformability and low fiber-fiber bonding. These results showed that paper made of hemp-wood pulp can be used for the specialty packaging paper which requires both the characteristic surface properties and the high physical strength of hemp fiber.

• Biomaterials Research
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• v.22 no.4
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• pp.346-351
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• 2018

Background: Carbonate apatite ($CO_3Ap$) and silica-calcium phosphate composite (SCPC) are bone substitutes with good prospect for dental application. SCPC creates a hydroxyapatite surface layer and stimulate bone cell function while, $CO_3Ap$ induce apatite crystal formation with good adaptation providing good seal between cement and the bone. Together, these materials will add favorable properties as a pulp capping material to stimulate mineral barrier and maintain pulp vitality. The aim of this study is to investigate modification of $CO_3Ap$ cement combined with SCPC, later term as $CO_3Ap-SCPC$ cement (CAS) in means of its chemical (Calcium release) and physical properties (setting time, DTS and pH value). Methods: The study consist of three groups; group 1 (100% calcium hydroxide, group 2 $CO_3Ap$ (60% DCPA: 40% vaterite, and group 3 CAS (60% DCPA: 20% vaterite: 20% SCPC. Distilled water was employed as a solution for group 1, and $0.2mol/L\;Na_3PO_4$ used for group 2 and group 3. Samples were evaluated with respect to important properties for pulp capping application such as pH, setting time, mechanical strength and calcium release evaluation. Results: The fastest setting time was in $CO_3Ap$ cement group without SCPC, while the addition of 20% SCPC slightly increase the pH value but did not improved the cement mechanical strength, however, the mechanical strength of both $CO_3Ap$ groups were significantly higher than calcium hydroxide. All three groups released calcium ions and had alkaline pH. Highest pH level, as well as calcium released level, was in the control group. Conclusion: The CAS cement had good mechanical and acceptable chemical properties for pulp capping application compared to calcium hydroxide as a gold standard. However, improvements and in vivo studies are to be carried out with the further development of this material.