• Title, Summary, Keyword: Tricalcium phosphate

Search Result 173, Processing Time 0.081 seconds

Tissue Engineered Bone Formation Using Porous Chitosan and Chitosan/Tricalcium Phosphate Matrices (Chitosan 및 Chitosan/Tricalcium Phosphate 다공성 기질을 이용한 조직공학적 골형성에 관한 연구)

  • Lee, Yong-Moo;Choi, Sang-Mook;Park, Yoon-Jeong;Lee, Seung-Jin;Ku, Young;Chung, Chong-Pyoung
    • Journal of Periodontal and Implant Science
    • /
    • v.28 no.4
    • /
    • pp.577-604
    • /
    • 1998
  • chitosan은 골치유증진 및 골세포의 분화를 촉진하는 것으로 알려진 천연의 생분해성 고분자이다. 이연구에서는 chitosan 및 chitosan/tricalcium phosphate(TCP) 다공성 기질을 제조하여 골이식재 및 조직공학적 골형성을 위한 3차원적 세포배양 지지체로서의 가능성을 평가하고자 하였다. chitosan 용액 및 TCP가 포함된 chitosan 용액을 동결건조함으로써 소공의 크기가 $100-200{\mu}m$인 스폰지형태의 chitosan 및 chitosan/TCP 다공성 기질을 제작하였다. 골이식재로서의 효과를 평가하기 위하여 백서의 두개골 결손부에 제작된 chiosan 및 chitosan/TCP 다공성 기질을 각각 이식하고 2주 및 4주 후에 동물을 희생하여 조직학적으로 치유양상을 관찰하였다. 조직공학적 골형성을 위한 세포배양 지지체로서의 가능성을 평가하기 위하여 백서 태자의 두개골에서 분리된 골아세포를 chitosan 및 chitosan/TCP 다공성 기질에 각각 접종하고 56일간 배양하면서 각 기간 별로 세포수, 염기성 인산효소 활성, 축적된 calcium의 양을 측정하였고 배양된 세포-기질 혼합체를 광학현미경 및 주사전자현 미경하에서 조직학적 관찰을 시행하였다. 백서 두개골결손부에 이식된 chitosan 및 chiosan/TCP 다공성 기질은 별다른 이물반응 없이 자연 분해되면서 신생골조직 내에 매립되었으며 이식하지 않은 대조군에 비해 유의하게 높은 신생골형성 효과를 나타내어 우수한 골전도성이 있음이 확인되었다. 신생골형성 양상이나 형성된 양에 있어서 두 가지 기질간의 유의한 차이는 없었다. 골아세포-기질 혼합체의 배양결과, 접종후 배양 28일 경과 시까지 골아세포수는 지속적으로 증가하다가 이후에는 5 8일까지 성장정도가 둔화되었다. 염기성 인산효소의 활성 및 calcium 축적량은 접종후 배양시간경과에 따라 56일까지 지속적으로 증가하였다. 세포수 및 염기성 인산효소의 활성에서 두 기질간의 유의한 차이는 없었고, calcium 축적량에 있어서는 chitosan/TCP 기질에서 유의하게 높았고 증가속도도 컸다. 배양된 골아세포가 접종된 다공성 기질의 조직학적 관찰결과, 골아세포는 다공성 기질에 잘 부착하여 중층의 형태로 성장하면서 광화된 골기질을 형성함이 관찰되었다. 배양 14일부터 작은 골편형태의 골형성이 기질 표면에 부착되어 관찰되었고, 배양기간이 길어짐에 따라 성장하여 배양 56일째에는 상당한 양의 광화된 골질이 형성됨이 관찰되었다. 배양 56일 경과후의 광화된 골질의 양은 chitosan/TCP 기질에서 더 많았다. 이 연구의 결과, chitosan 및 chitosan/TCP 다공성 기질이 골이식재로서 뿐만 아니라, 조직공학적 골형성에 적용되는 골아세포의 배양을 위한 3차원구조의 세포지지체로 이용되어 골재생술식에 유용한 생체재료로 활용될 수 있음이 확인되었다.

  • PDF

Synthesis and Properties of Self-hardening Calcium Phosphate Cemetns for Biological Application

  • Song, Tae-Woong;Kim, Han-Yeop
    • The Korean Journal of Ceramics
    • /
    • v.3 no.2
    • /
    • pp.129-133
    • /
    • 1997
  • Fine powder of $\alpha$-tricalcium phosphate, tetracalcium phosphate and dicalcium phosphate were mixed together to prepare self-setting cements which form hydroxyapatite, one of the well-known biocompatible materials, as the end of products of hydration. Hardening behaviour of the cements was examined at the temperature range of 37~$70^{\circ}C$ and 150~$250^{\circ}C$ under the normal and hydrothermal condition respectively. The conversion of cements into hydroxyapatite was significantly improved ast elevated temperature and the paste was strengtheed by interlocking of hydroxyapatite crystals, indicating that the strength is determined by microtexture rather the amount of conversion of cements into hydroxyapatite.

  • PDF

Phase Developments and Microstructure Changes of Calcium Phosphate Powders Synthesized by Recycling Eggshell (달걀껍질의 재 사용에 의해 제조 된 생체용 Calcium Phosphate 분말의 상변화 거동 및 미세구조 변화에 관한 연구)

  • Lee Sang-Jin;Kim Joo-Won
    • Journal of Korean Powder Metallurgy Institute
    • /
    • v.11 no.5
    • /
    • pp.391-398
    • /
    • 2004
  • Calcium phosphate powders were successfully synthesized by using re-cycled eggshell and phosphoric acid. The crystallization behavior and powder morphologies of the synthesized powders were dependent on the starting condition of the eggshell, the mixing ratio and method of the eggshell and phosphoric acid, and calcination temperature. In general, $\beta$-tricalcium phosphate was stably synthesized at about $900^{\circ}C$ for 1h at each proper mixing ratio. And, the synthesized powders showed the similar microstructures to the morphology of original eggshell with uniform particle sizes. In this study, the calcium phosphate powders were synthesized with eggshell in various processing method. And their unique microstructures obtained from the eggshell were also. observed. The crystalline developments and microstructures of the synthesized powders were examined by X-ray diffractometer and scanning electron microscopy.

Precipitation of Calcium Phosphate at pH 5.0 for the β Tri-calcium Phosphate Cement

  • Chang, Myung Chul
    • Journal of the Korean Ceramic Society
    • /
    • v.50 no.4
    • /
    • pp.275-279
    • /
    • 2013
  • The purpose of this study was to prepare calcium phosphate cement [CPC] for use in artificial bone. Nano-crystalline calcium phosphate [CaP] was precipitated at $37^{\circ}C$ using highly active $Ca(OH)_2$ in DI water and an aqueous solution of $H_3PO_4$. From the XRD measurements, the nano-CaP powder was close to apatitic TCP phase and the powders fired at $800^{\circ}C$ showed a critical ${\beta}$-TCP phase. A mixture of one mole $CaCO_3$ and two moles di-calcium phosphate was calcined at $1100^{\circ}C$ to make a reference ${\beta}$-TCP material. The nano-CaP powders were added to the normal ${\beta}$-TCP matrix and fired at $900^{\circ}C$ to make a ${\beta}$-TCP block. The sintered block showed improved mechanical strength, which was caused by the solid state interaction between nano-CaP and normal ${\beta}$-TCP.

Isolation and Identification of Phosphate Solubilizing Bacteria from Chinese Cabbage and Their Effect on Growth and Phosphorus Utilization of Plants

  • Poonguzhali, Selvaraj;Madhaiyan, Munusamy;Sa, Tong-Min
    • Journal of Microbiology and Biotechnology
    • /
    • v.18 no.4
    • /
    • pp.773-777
    • /
    • 2008
  • Phosphate solubilizing bacteria (PSB) were isolated from the rhizosphere of Chinese cabbage and screened on the basis of their solubilization of inorganic tricalcium phosphate in liquid cultures. Ten strains that had higher solubilization potential were selected, and they also produced indole-3-acetic acid, 1-aminocyclopropane-1-carboxylate (ACC) deaminase, and siderophores. The strains were identified to be members of Pseudomonas, by 16S rDNA sequence analysis. Seed bacterization with PSB strains increased the root elongation and biomass of Chinese cabbage in seedling culture, although they had no effect on phosphorus uptake of plants. The plant growth promotion by PSB in this study could be due to the production of phytohormones or mechanisms other than phosphate solubilization, since they had no effect on P nutrition.

Therapeutic Effect of Toothpaste Containing Hydroxyapatite and Tribasic Calcium Phosphate on Dentinal Hypersensitivity (치아 과민증에 Hydroxyapatite와 Tricalcium phosphate을 함유한 치약의 치료효과)

  • Choi, Yea Hun;Park, Hyean Cheal;Lee, Sang Mong;Son, Hong Joo;Choi, Eun Bi;Ha, Jun Young;Lee, Jun Young;Kim, Keun Ki
    • Journal of Life Science
    • /
    • v.24 no.6
    • /
    • pp.642-647
    • /
    • 2014
  • Although it is not a pathological symptom, Dentinal Hypersensitivity (DH) describes pain felt by patients whose tooth roots are exposed outside of the gums and are therefore sensitive to external stimuli. DH is caused by tooth brushing or gum diseases and treatment to reduce the sensitivity can include use of materials having stimulation activity for DH or a resin material applied periodontally. This study examined the hypersensitivity treatment effects of a four-week treatment with a toothpaste containing hydroxyapatite and tricalcium phosphate (Hap-TCP toothpaste). The Hap-TCP toothpaste was made by mixing a commercially available fluorine-containing toothpaste with 10% (W/W) hydroxyapatite and 19% (W/W) tricalcium phosphate (both 99% purity based on XRD analysis). The tooth hypersensitivity treatment effect was surveyed by scoring VRS values, and showed no significant initial difference compared with the control. However, after 1 week of use, the pain reduction value was 8% in the treatment group compared to the control group. This value increased to 30% and 60% after 2 and 4 weeks, respectively. Hypersensitivity to cold stimulation, which was used as a VAS value, showed no initial significant differences compared with the control, but was significantly decreased after 1, 2, and 4 weeks in the experimental group, with more than a 3-fold difference after 4 weeks. These findings confirmed that remineralization can alleviate DH as hydroxyapatite fills dentinal tubules and calcium, phosphorus, and tricalcium phosphate ion equilibrium is established.

Study on the Sinterability of Silicon Substituted Hydroxyapatite (Si 치환 Hydroxyapatite의 소결 특성에 관한 연구)

  • Lee, Yoon-Joo;Kim, Young-Hee;Kim, Soo-Ryong;Jung, Sang-Jin;Riu, Do-Hyung;Song, Hee;Jun, Moo-Jin
    • Journal of the Korean Ceramic Society
    • /
    • v.40 no.11
    • /
    • pp.1096-1101
    • /
    • 2003
  • Si -substituted hydroxyapatite has been prepared to obtain biomaterials having an improved biocompatibility. From FT-IR, XRD, and ICP analyses, it was confirmed that the single-phase of hydroxyapatite substituted by Si has formed. Si- substituted hydroxyapatite of up to 2 wt% for Si keeps its original structures intact for the sintering temperatures of up to 1200$^{\circ}C$. However, it is observed that the ion substitutions by the amount higher than the above ratios for the hydroxyapatite leads to destabilize original structures of the hydroxyapatite and to produce tricalcium phosphate and calcium phosphate silicate phases when the samples were sintered at 1l00$^{\circ}C$ or higher.

A STUDY ON THE CYTOTOXICITY OF THE ROOT CANAL SEALERS (근관충전용(根管充塡用) sealer의 세포독성(細胞毒性)에 관한 연구(硏究))

  • Lee, Seung-Jong;Kim, Yung-Hai
    • Restorative Dentistry and Endodontics
    • /
    • v.16 no.1
    • /
    • pp.25-40
    • /
    • 1991
  • Four root canal sealers, Apatite Root Sealer I and II composed mainly of hydroxyapatite/tricalciumphosphate, Sealapex containing calcium hydroxide, and Roth Sealer composed of zinc oxide - eugenol were compared on the culture of L929 fibroblasts. MIT (Methyl Thiazole Tetrazolium Bromide) colorimetric technique was used to measure the mitochondrial dehydrogenase activity. Results were as follows: 1. Hydroxyapatite/tricalcium phosphate mixed sealers were significantly less toxic compared with calcium hydroxide and zinc oxide - eugenol type sealers. High pH of the calcium hydroxide sealer and release of eugenol component from the zinc oxide - eugenol type sealer were presumed to be the cause of the toxicity of these two sealers. In no cases, there were more cytoblastic effects in hydroxyapatite/tricalcium phosphate mixed sealers compared to the control groups. 2. In all experimental groups, toxicity was decreased as dilutions were increased. However in zinc oxide-eugenol type sealer the cell activity was weakened for all dilution groups. 3. Regarding the effect of setting time, Apatite I and Sealapex were less toxic as the setting progressed. Apatite II kept constant regardless of the different time ellapsed after setting but Roth sealer revealed significantly higher toxicity for all experimental groups. 4. Comparing two different culture periods of 24 hours and 72 hours, Apatite I showed higher cell activities in longer period(72 hours) while Apatite II did not. Sealapex and Roth sealer, however, showed significantly lower cell activities in longer period.

  • PDF

Effect of Feeding Live Yeast (Saecharomyces cerevisiae) on Nutrient Utilization and Changes of Intestinal Microorganism in Broiler Chicks (육계에 있어서 활성효모 (Saccharomyces cerevisiae)의 급여가 영양소 이용성과 장내 미생물의 변화에 미치는 영향)

  • 이현우;김인호;김춘수
    • Korean Journal of Poultry Science
    • /
    • v.22 no.4
    • /
    • pp.203-211
    • /
    • 1995
  • In order to investigate the effect of feeding live yeast on growth performance, nutrients utilization, tibia mineral deposit and intestinal microorganism changes, a growth assay was conducted with 360 broiler chicks. Treatments were four levels of yeast as 0, 0.025, 0.05 and 0.1% in 1.83% tricalcium phosphate and two levels of yeast as 0 and 0.05% in 1.15% tricalcium phosphate. The crude protein content of live yeast was 45%, and 97% of it was in the pure protein form, with 46.6% of essential amino acids and 53.4% of non-essential amino acids. Growth performance was tended to increase by feeding the yeast but there was no significant difference(P>.05). The protein digestibility was increased as the feeding level of yeast increased. However, digestibilities of fat, fiber, calcium and phosphorus were not affected by the yeast. Ash and calcium content of tibia were increased as the level of yeast increased. Total number of E. coli in small intestine was significantly decreased(P<.05) in chicks fed yeast. Total number of Lactobaci1lus was significantly increased by the yeast feeding. The changes of microorganism in cecum had the same trend with the changes of microorganism in small intestine.

  • PDF