• Title/Summary/Keyword: biomaterials

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Healing patterns after guided bone regeneration in human extraction sockets (인간의 발치와 내에서 골유도재생술 후의 치유양상)

  • Jang, Hyun-Seon;Yeom, Chang-Yeob;Park, Joo-Cheol;Kim, Su-Gwan;Kim, Heung-Joong;Kook, Joong-Ki;Kim, Chong-Kwan;Kim, Byung-Ock
    • Journal of Periodontal and Implant Science
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    • v.35 no.4
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    • pp.949-959
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    • 2005
  • 이 연구는 임플란트를 식립하기를 원하는 전신건강상태가 양호하며 구강위생상태가 좋은 14명 환자(남자:8명, 여자:6명, 평균나이 : 44세)의 20개의 발치와 내에 흡수성 차폐막(BioMesh. Sam Yang Corporation, Korea)과 함께 탈회냉동 건조동종 골(dem-ineralized freezedried bone allografts, $250-500{\mu}m$. Pacific Coast Tissue Bank, U.S.A.)과 이종골(Bovine-Bone, Bio-Oss 0.25-1.0 mm, Geistlich, Biomaterials and Osteohealth, Switzerland)을 1:1(부피)로 혼합하여 이식한 후 그 치유양상을 관찰하고자 조직학적 및 면역조직화학적으로 평가하였다. 이직재가 탈락되는 것을 방지하기 위하여 발치한 후 1개윌이 경과된 후에 이식재와 차폐막을 위치시켰다. 표본제작을 위하여 이식술을 시행한 지 약 6개윌 후에 임플란트를 식립하기 직전 식립부위에서 trephine bur로 골을 채취하였는데, 20증례 중 7증례에서 임플란트를 식립하기 전에 차폐막이 노출되었다. 차폐막이 노출되지 않은 것을 대조군으로, 노출된 것을 실험군으로 설정하였다. 조직학적인 관찰을 위하여 통상적인 방법에 따라 탈회 표본을 제작하였고, alkaline phosphotase(ALP)틀 이용하여 면역조직화학적 염색을 시행한 후 골 형성 상태를 평가하여 다음과 같은 결과를 얻었다. 본 연구에서는 발치와내에서 골유도재생술 후 나타나는 치유 형태를 5가지 형태로 분류할 수 있었다. Type I, II와 III는 새로운 골 형성을 나타내지 않았고, 면역조직화학적 검사 시 ALP 음성 소견을 나타내었다. Type V는 새로운 골 형성과 ALP 양성 소견을 나타내었으나 염증, 괴사, 결합조직의 증식 등은 없었다. Type IV와 Type V의 차이는 결합조직의 증식여부로 구분되었다. 막이 노출되지않은 증례들 중 7 증례에서는 Type V의 치유 형태를, 2증례에서는 Type IV의 치유 형태를 나타내었다. 막이 노출되었던 증례에서는 Type I, II, III의 다양한 치유 형태를 나타내었다. 본 연구결과, 발치와 내에 골유도재생술을 시행한 후 차폐막의 노출 여부가 신생골 형성에 중요한 영향을 미칠 것으로 사료되며, 본 연구에서 분류한 치유 형태가 향후 골유도재생술 후의 결과 분석에 활용될 수 있을 것으로 사료된다.

Histologic evaluation of various membranes on periodontal tissue regeneration of 1-wall intrabony defects in dogs (성견 1벽성 골내낭 결손부의 조직재생에 대한 수종의 차폐막의 조직학적 평가)

  • Yang, Jin-Hyuk;Chae, Gyung-Joon;Yun, Jeong-Ho;Song, Si-Eun;Lee, Yong-Keun;Cho, Kyoo-Sung;Kim, Chong-Kwan;Choi, Seong-Ho
    • Journal of Periodontal and Implant Science
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    • v.38 no.1
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    • pp.51-58
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    • 2008
  • Purpose: In dental clinical fields, various periodontal membranes are currently used for periodontal regeneration. The periodontal membranes are categorized into two basic types: resorbable and non-resorbable. According to the case, clinician select which membrane is used. Comparing different membranes that are generally used in clinic is meaningful. For this purpose, this study evaluates histological effects of various membranes in canine one wall intrabony defect models and it suggest a valuation basis about study model. Material and Method: The membranes were non-resorbable TefGen $Plus^{(R)}$, resorbable Gore Resolut $XT^{(R)}$ and resorbable $Osteoguide^{(R)}$. One wall intrabony defects were surgically created at the second and the mesial aspect of the fourth mandibular premolars in either right or left jaw quadrants in two dogs. The animals were euthanized 8 weeks post-surgery when block sections of the defect sites were collected and prepared for histological evaluation. Results: 1. While infiltration of inflammatory cells were observed in control, TefGen $Plus^{(R)}$ and Gore Resolut $XT^{(R)}$, it was not observed in $Osteoguide^{(R)}$. 2. TefGen $Plus^{(R)}$ had higher integrity than others and $Osteoguide^{(R)}$ was absorbed with folding shape. Gore Resolut $XT^{(R)}$ was divided everal parts during resorbtion and it was also absorbed from inside. 3. Quantity of new bone and new cementum was not abundant in all membranes. 4. For histologic evaluation of membranes we should consider infiltration of inflammatory, migration of junctional epithelium, integrity of membrane, quantity of new bone and new cementum, connective tissue formation and aspect of resorption. Conclusion: This histologic evaluation suggests that $Osteoguide^{(R)}$ provides periodontal regenerative environment with less inflammatory state. It is meangful that this study model suggests a valuation basis about other study model.

Study of chitosan's effects on periodontal tissue regeneration: a meta-analysis of the histomorphometry (키토산의 치주조직 재생력에 대한 연구의 고찰: 조직계측학적 메타분석)

  • Yang, Jin-Hyuk;Chae, Gyung-Joon;Yun, Jeong-Ho;Jung, Ui-Won;Lee, Yong-Keun;Cho, Kyoo-Sung;Chai, Jung-Kiu;Kim, Chong-Kwan;Choi, Seong-Ho
    • Journal of Periodontal and Implant Science
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    • v.38 no.1
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    • pp.7-14
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    • 2008
  • Purpose: Chitosan & chitosan derivative(eg. membrane) have been studied in periodontal regeneration, and recently many studies of chitosan have reported good results. If chitosan's effects on periodontal regeneration are enhanced, we can use chitosan in many clinical and experimental fields. For this purpose, this study reviewed available literatures, evaluated comparable experimental models. Materials and Methods: Ten in vivo studies reporting chitosan's effects on periodontal tissue regeneration have been selected by use of the 'Pubmed' and hand searching. Results: 1. In Sprague Dawley rat calvarial defect models, amount of newly formed bone in defects showed significant differences between chitosan/chitosan-carrier/chitosan-membrane groups and control groups. 2. In beagle canine 1-wall intrabony defect models, amount of new cementum and new bone showed significant differences between chitosan/chitosan-membrane groups and control groups. The mean values of the above experimental groups were greater than the control groups. Conclusion: The results of this study have demonstrated that periodontal regeneration procedure using chitosan have beneficial effects, which will be substitute for various periodontal regenerative treatment area. One step forward in manufacturing process of chitosan membrane and in use in combination with other effective materials(eg. bone graft material or carrier) may bring us many chances of common use of chitosan in various periodontal area.

The Characteristics and Survival Rates of Evergreen Broad-Leaved Tree Plantations in Korea (난대상록활엽수종 조림지 활착률과 영향인자)

  • Park, Joon-Hyung;Jung, Su-Young;Lee, Kwang-Soo;Lee, Ho-Sang
    • Journal of Korean Society of Forest Science
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    • v.108 no.4
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    • pp.513-521
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    • 2019
  • With rapid climate change and increasing global warming, the distribution of evergreen broad-leaved trees (EBLTs) is gradually expanding to the inland regions of Korea. The aim of the present study was to analyze the survival rate of 148 EBLT plantations measuring 180 ha and to determine the optimal plantation size that would help in coping with climate change in the warm, temperate climate zone of the Korean peninsula. For enhancing the reliability of our estimated survival model, we selected a set of 11 control variables that may have also influenced the survival rates of the EBLTs in the 148 plantations. The results of partial correlation analysis showed that the survival rate of 67.0±26.9 of the EBLTs in the initial plantation year was primarily correlated with plantation type by the crown closure of the upper story of the forest, wind exposure, and precipitation. For predicting the probability of survival by quantification theory, 148 plots were surveyed and analyzed with 11 environmental site factors. Survival rate was in the order of plantation type by the crown closure of upper story of the forest, wind exposure, total cumulative precipitation for two weeks prior to planting, and slope stiffness in the descending order of score range in the estimated survival model for the EBLTs with the fact that survival rate increased with shade rate of upper story to some extent.

Protective Effects of Green Tea Seed Extract against UVB-irradiated Human Skin Fibroblasts (인체 피부 섬유아세포에서 자외선 조사에 대한 녹차나무 씨 추출물의 보호효과)

  • Kim, Ok Kyung;Nam, Da-Eun;Lee, Min-Jae;Kang, Namgil;Lim, Jae-Youn;Lee, Jeongmin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.1
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    • pp.1-8
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    • 2014
  • In this study, we investigated the protective effects of green tea seed extract (GSE) against UVB-induced skin damage in human skin fibroblasts. GSE was first analyzed for antioxidant activity using 1,1-diphenyl-2picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging assays. Treatment of UV-irradiated fibroblast with GSE at 10~50 ${\mu}g/mL$ significantly increased DPPH and ABTS radical scavenging activities in a dose-dependent manner. GSE treatment inhibited matrix metalloproteinase (MMP-1, MMP-3, and MMP-9) expression and MMP-1 secretion caused by UVB irradiation. Moreover, treatment with GSE significantly increased type-1 collagen expression and production. We next examined levels of antioxidative enzymes (SOD, catalase, and GPx). Reduced antioxidative enzyme activities caused by UVB irradiation were recovered by treatment with GSE at 30 ${\mu}g/mL$ and 50 ${\mu}g/mL$. In conclusion, these results show that GSE has protective effects against UVB-induced skin damage in human skin fibroblasts by regulating antioxidative defense systems and MMP expression.

The Short-term Effects of Soil Brought and Subsoil Inversion on Growth and Tissue Nutrient Concentrations of Fraxinus rhynchophylla, Pinus densiflora, and Pinus koraiensis Seedlings in a Nursery (객토와 심토뒤집기 처리가 물푸레나무, 소나무, 잣나무 묘목의 초기 생장과 양분함량에 미치는 영향)

  • An, Ji Young;Park, Byung Bae;Byun, Jae Kyung;Cho, Min Seok;Kim, Yong Suk;Han, Si Ho;Kim, Se Bin
    • Journal of Korean Society of Forest Science
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    • v.104 no.1
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    • pp.43-49
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    • 2015
  • The production of high quality seedlings is a very important phase in silvicultural systems for successful reforestation or restoration. The purpose of this study was to quantitatively measure both growth performances and nutrient responses of Fraxinus rhynchophylla, Pinus densiflora, and Pinus koraiensis seedlings, which are commercially planted in Korea, according to the different types of soil improvement treatments. We applied soil brought (hereafter 'brought'), subsoil inversion (hereafter 'subsoil'), and mixture of brought soil with soil on nursery bed (hereafter 'mixing') in a permanent national nursery. Silt and clay contents were the highest at the subsoil treatment and organic material, soil nitrogen and phosphorus concentrations were the lowest at the brought treatment. The growth of F. rhynchophylla was the lowest at the subsoil treatment, but there were no significant differences among treatments. There were significant differences in only root nutrient concentrations of F. rhynchophylla among treatments: nitrogen, phosphorus, and potassium concentrations were the lowest at the subsoil or brought treatment. Mixing treatment increased N contents with deduction of N concentrations ('dilution') because of more dry weight increase compared with the amount of N uptake. This study suggested mix of brought soil with soil on a nursery bed in a permanently used nursery can economically be an effective technique to improve soil quality.

Effect of Fiber Type and Combination on the Reinforcement of Heat Polymerized Denture Base Resin (섬유의 종류와 조합이 열중합 의치상 레진의 강화에 미치는 영향)

  • Yu, Sang-Hui;Kim, Young-Im
    • Journal of dental hygiene science
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    • v.10 no.6
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    • pp.445-450
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    • 2010
  • The aim of this study was to evaluate the effect according to the fiber type and combination on the reinforcement of heat-polymerized denture base resin. The heat-polymerized resin(Vertex RS, Dentimax, Netherlands) was used in this study. Glass fiber(GL; ER 270FW, Hankuk Fiber Glass, Korea), polyaromatic polyamide fiber(PA; aramid; Kevlar-49, Dupont, U.S.A.) and ultra high molecular weight polyethylene fiber(PE, polyethylene; P.E, Dong Yang Rope, Korea) were used to reinforce the denture base resin specimens. The final size of test specimen was $64mm{\times}10mm{\times}3.3mm$. The specimens of each group were stored in distilled water at $37^{\circ}C$ for 50 hours before measurement. The flexural strength and flexural modulus were measured by an universal testing machine(Z020, Zwick, Germany) at a crosshead speed of 5 mm/min in a three-point bending mode. In this study, all fibers showed reinforcing effects on denture base resin(p<0.05). In terms of flexural strength and flexural modulus, glass fiber 5.3 vol.% showed most effective reinforcing effect on heat polymerized denture base resin. For flexural modulus, PA/GL was the highest in denture base resin specimen for hybrid FRC using two combination (p<0.05). Glass fiber 5.3 vol.% and PA/GL are considered to be applied effectively in reinforcing the heat polymerized denture base resin.

Enhancement of the Cosmeceutical Activity by Nano-encapsulation of Thiamine Di-lauryl Sulfate (TDS) with antimicrobial efficacy (항균 효능이 있는 비타민 B1 유도체(Thiamine Dilauryl Sulfate:TDS)의 나노입자화를 통한 기능성 향장 활성 증진)

  • Seo, Yong Chang;No, Ra Hwan;Kwon, Hee-Seok;Lee, Hyeon Yong
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.39 no.3
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    • pp.205-213
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    • 2013
  • This study was to improve cosmetical activity of thiamine di-lauryl sulfate (TDS) by encapsulation of nanoparticle with lecithin. Results showed that most of the nanoparticles containing the TDS were well formed in round shape with below 150 ~ 200 nm diameter as well as they were fairly stable in various pH ranges by measuring zeta potentials. The nanoparticles of TDS resulted in 85% cell viability of human normal fibroblast cells (CCD-986sk) when added at the highest concentration (1.0 mg/mL). The nanoparticles of Acer mono sap showed highest free radical scavengering effect as 88.1% in adding sample (1.0 mg/mL), compared to TDS solution of non-encapsulation (81.6%). The nanoparticles of TDS reduced the expression of MMP-1 on UV-irradiated CCD-986sk cells down to as 41.4%. The TDS solution and nanoparticles showed significant anti-microbial activities agaionst the salmonella typhimurium and listeria monocytogenes at 5 and 6 days as compared with control. Anti-microbial activities of TDS nanoparticles were similar to positive control. These results indicated that TDS nanoparticles may be a source for functional cosmetic agents capable of improving cosmetical activity such as antioxidant, whitening, and anti-wrinkling effects and can be further developed as natural preservative in cosmetics.

Analysis of Immunomodulating Activities in Methanol Extracts from Several Kinds of Grapes (포도 품종별 메탄올 추출물로부터 면역활성 분석)

  • Heo, Jin-Chul;Woo, Sang-Uk;Kweon, Mi-Ae;Kim, Bo-Bae;Lee, Sook-Hee;Lee, Jin-Man;Choi, Jong-Uck;Chung, Shin-Kyo;Lee, Sang-Han
    • Food Science and Preservation
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    • v.14 no.4
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    • pp.419-424
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    • 2007
  • Fruits and vegetable extracts are well-known as healthy foods. Such foods have been used as herbal medicines or traditional therapies for centuries. To assess biological activities in grapes, we examined the immunomodulating activities of water extracts from four kinds of grapes (cultivars Kyoho, Delaware, Campbell, and Niagara). We explored possible antioxidant and anticancer activities using antioxidant assays such as the 1,1-diphenyl-2-picrylhydrazyl (DPPH) reduction assay, the ferric iron reducing ability of plasma (FRAP) assay, a cell proliferation assay, an NO inhibition assay, a wound healing assay, and an IL-4/IL-13 elicitation assay. Methanol extracts of grapes were tested. The results showed that each grape extract had potent antioxidant activities. The grape extracts increased cell proliferation and NO production activities in tumor cell lines. IL-4 and IL-13 cytokine levels were decreased in mouse primary spleen cells by treatment with any extract. These results suggest that grape extracts can be used as biomaterials with immunomodulating activities.

In vitro Antibacterial Effect of Orthodontic Adhesives Mixed with Silver Nanoparticles

  • Choi, Kwon-Yong;Lee, Jong-Chan;Hwang, Yun-Chan;Chang, Seok-Woo;Kum, Kee-Yeon;Bae, Kwang-Shik;Lim, Bum-Soon;Paeng, Jun-Young;Kim, Eun-Cheol;Kwon, Ho-Beom;Kim, Young-Ho
    • Journal of Korean Dental Science
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    • v.5 no.1
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    • pp.7-12
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    • 2012
  • Purpose: To examine the antibacterial effectiveness of silver nanoparticles (SNP) mixed with commercial orthodontic adhesives. Materials and Methods: SNP was prepared by dissolving silver perchlorate in an organic solvent and reducing it with ultraviolet radiation. SNP was then mixed with four commercial orthodontic adhesives (Light Bond, Blugloo, Transbond XT, and Fuji Ortho LC) (0.05 wt %), which were then formed into disc-shape specimens ($8.0mm{\times}3.0mm$). Commercial orthodontic adhesives containing no SNP were used as the control groups. Specimens of the four experimental and four control groups were incubated with streptococcus mutans and the medium turbidity was assessed at 3, 6, 9, 12, and 24 hours after incubation. The agar diffusion test was also performed to examine the growth inhibition zone of these groups. The data were statistically analyzed using a Wilcoxon rank sum test and t-test with a Bonferroni's correction (P<0.05). Result: The SNP containing groups had a superior antibacterial effect compared to the control groups. In the agar diffusion test, the control groups without SNP did not produce an inhibition zone, whereas the SNP containing groups showed inhibition zone of 10~13 mm. Conclusion: The incorporation of SNP into orthodontic adhesives can inhibit cariogenic bacterial growth.