• 한국재료학회:학술대회논문집
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• 한국재료학회 2009년도 추계학술발표대회
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• pp.40.2-40.2
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• 2009

Using the favorable resorption behavior of amorphous Calcium phosphate (CaP) we fabricated a gelatin basednano fibrous mat by electrospinning for using as a fast healing patch for minorbone defects. Bone is predominantly formed by an inorganic phase of nano-crystalline HAp materials and nano fibrous protein material of collagen. The osteoblast cells, which are the bone formation cells and are key to the new bone formation, receive these materials to form new bone. Taking these considerations we make a new nano fibrous mat of amorphous CaP and gelatin, which is derived from collagen itself. A polymer carrier of poly caprolactone(PCL) was used in the system to stabilize the materials in biological condition. The electrospinning conditions were optimized for smooth mat without any droplet formation. The fabricated mat was characterized for its morphologyby SEM. Mechanical properties like tensile strength was evaluated. To investigate the bio-compatibility we performed the MTT assay and investigated its resorption behavior and apatite formation behavior by SBF immersion.

• Journal of Periodontal and Implant Science
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• 제40권3호
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• pp.125-131
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• 2010

Purpose: Among available biomaterials, bioceramics have drawn special interest due to their bioactivity and the possibility of tailoring their composition. The degradation rate and formulation of bioceramics can be altered to mimic the compositions of the mineral phase of bone. The aim of this study was to investigate the bone formation effect of amorphous calcium phosphate glass cement (CPGC) synthesized by a melting and quenching process. Methods: In five male beagle dogs, $4{\times}4$ mm 1-wall intrabony defects were created bilaterally at the mesial or distal aspect of the mandibular second and fourth premolars. Each of the four defects was divided according to graft materials: CPGC with collagen membrane (CM), biphasic calcium phosphate (BCP) with CM, CM alone, or a surgical flap operation only. The dogs were sacrificed 8 weeks post-surgery, and block sections of the defects were collected for histologic and histometric analysis. Results: There were significant differences in bone formation and cementum regeneration between the experimental and control groups. In particular, the CPGC and BCP groups showed greater bone formation than the CM and control groups. Conclusions: In conclusion, CPGC was replaced rapidly with an abundant volume of new bone; CPGC also contributed slightly to regeneration of the periodontal apparatus.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.484-485
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• 2006

The process of coprecipitation of biocomposite hydroxyapatite/chitosan from aqueous solution at low temperature in alkali environnement was examined. We have shown that initially we have the formation of amorphous octocalcium phosphates $(Ca_8(HPO_4)(PO_4)_5,\;nH_2O:\;OCP)$ and the transferring from OCP to amorphous calcium phosphate $(Ca_9(PO_4)_3,\;nH_2O:\;TCP)$, and then from TCP to calcium-deficient hydroxyapatite $(Ca_{10-X}\;(HPO_4)_X(PO_4)_{6-x}(OH)_{2-X}\;:\;ACP)$ and hydroxyapatite $(Ca_{10}(PO_4)_6(OH)_2\;:\;HAP)$. The transformation of ACP to HAP was inhibited in the presence of chitosan. The result suggests that there is an affinity binding between ACP and chitosan and subsequently blocking the active growth site of ACP.

• 한국치위생학회지
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• 제10권3호
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• pp.473-481
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• 2010

Objectives : To evaluate the effect of fluoride application on the color and microhardness of bleached enamel and compare it to that of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) application. Methods : Twenty freshly extracted human adult molar were each sectioned into halves, the specimens divided and treated according to five experimental groups: Group 1, treatment with 10% carbamide peroxide (CP) bleaching agent; Group 2, treatment with 10% CP followed by a 1.23% fluoride gel application; Group 3, treatment with 10% CP followed by a 2.23% sodium fluoride varnish application; Group 4, treatment with 10% CP followed by a 0.11% sodium fluoride gel application; Group 5, treatment with 10% CP followed by a CPP-ACP gel application. All groups were treated 6 h per day for 14 days then immersed in distilled water for 2 weeks. Changes in enamel color were evaluated on Baseline and Day 14. Microhardness were evaluated on Baseline, Days 7 and 14. Statistical analysis was performed using one-way ANOVA and post-hoc Tukey tests. Results : All the bleached enamel specimens revealed increased whiteness and overall color value. Group 1 showed the lowest microhardness values than that of Groups 2, 3, 4 and 5. In all groups, the hardness of tooth after bleaching showed a significant decrease in the microhardness as compared with the one prior to tooth bleaching. The specimens treated with remineralizing agents showed relatively less reduction in enamel microhardness than control group. Conclusions : The addition of fluoride and CPP-ACP did not impede the whitening effect. The use of remineralizing agents during bleaching treatment can significantly enhance the microhardness of bleached enamel.

• 대한소아치과학회지
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• 제41권3호
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• pp.218-224
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• 2014

이 논문은 법랑질의 표면미세경도와 QLF의 ${\Delta}F$ 값의 변화를 분석하여 5% 불화나트륨을 함유한 고분자 접착 테잎(NaF-PVA)이 법랑질의 재광화에 미치는 영향을 평가하고자하였다. 시편을 탈회한 후 표면미세경도가 평균 50-100 KHN의 범위를 갖고 QLF의 ${\Delta}F$ 값이 -25에서 -15 범위를 갖는 60개의 시편들을 4그룹으로 나누었다 : 그룹1(대조군), 그룹2(NaF-PVA), 그룹3(불소바니쉬, FluoroDose$^{(R)}$ varnish), 그룹4(Casein phosphopeptide-amorphous calcium phosphate, Tooth mousse plus$^{TM}$). 시편들에 각 제제들을 적용하고 인공타액(artificial saliva)에 담근 후 표면미세경도계와 정량 광 형광기를 이용하여 재광화율을 측정하였다. 그 결과 불소를 함유한 고분자 접착 테잎(NaF-PVA)은 그룹1과 4보다 뛰어나며 그룹3과 견줄만한 재광화 효과를 나타냈다 (p<0.05).

• 대한치과교정학회지
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• 제43권1호
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• pp.23-28
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• 2013

Objective: The purpose of this study was to evaluate the effect of casein phosphopeptide amorphous calcium phosphate (CPP-ACP) on the shear bond strength (SBS) of brackets bonded to non-demineralized teeth with either phosphoric acid etching or self-etching primer. Methods: Sixty human premolars were randomly assigned to 1 of 4 treatment groups (n = 15 each): phosphoric acid etching (group 1); self-etching primer (group 2); CPP-ACP for 2 weeks + phosphoric acid etching (group 3), and CPP-ACP for 2 weeks + self-etching primer (group 4). After bonding of the maxillary premolar metal brackets, specimens were subjected to shear forces in a testing machine. Scanning electron microscopy was used to observe etching patterns on the enamel surfaces of all teeth. A 2-way analysis of variance was used to test for effects of CPP-ACP and etching system on SBS. Results: Significantly higher mean SBSs were observed in groups subjected to phosphoric acid etching (i.e., groups 1 and 3; p < 0.05). On the other hand, SBSs did not appear to be influenced by CPP-ACP (i.e., groups 3 and 4; p > 0.05). We observed a uniform and clear etched pattern on the enamel surface of the phosphoric acid etching groups. Conclusions: CPP-ACP does not significantly affect the SBS of orthodontic brackets bonded to non-demineralized teeth, regardless of which adhesive method is used to bond the brackets.

• Restorative Dentistry and Endodontics
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• 제43권4호
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• pp.45.1-45.11
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• 2018

Objectives: This study was conducted to evaluate fluoride release and the micro-shear bond strength of resin-modified glass ionomer cement (RMGIC) in casein phosphopeptide-amorphous calcium phosphate (CPP-ACP)-remineralized caries-affected dentin (CAD). Materials and Methods: Exposed dentin surfaces of 30 human third molar teeth were divided into 2 equal groups for evaluating fluoride release and the micro-shear bond strength of RMGIC to CAD. Each group was subdivided into 3 equal subgroups: 1) control (sound dentin); 2) artificially demineralized dentin (CAD); 3) CPP-ACP remineralized dentin (remineralized CAD). To measure fluoride release, 15 disc-shaped specimens of RMGIC (4 mm in diameter and 2 mm in thickness) were bonded on one flat surface of the dentin discs of each group. Fluoride release was tested using ion chromatography at different intervals; 24 hours, 3, 5, 7 days. RMGIC micro-cylinders were built on the flat dentin surface of the 15 discs, which were prepared according to the assigned group. Micro-shear bond strength was measured after 24 hours water storage. Data were analyzed using 1- and 2-way analysis of variance and the post hoc least significant difference test (${\alpha}=0.05$). Results: Fluoride detected in solutions (at all intervals) and the micro-shear bond strength of RMGIC bonded to CPP-ACP-remineralized dentin were significantly higher than those bonded to artificial CAD (p < 0.05). Conclusions: Demineralized CAD consumes more fluoride released from RMGIC into the solution for remineralization than CPP-ACP mineralized dentin does. CPP-ACP increases the micro-shear bond strength of RMGIC to CAD.

• 대한소아치과학회지
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• 제43권4호
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• pp.391-400
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• 2016

본 연구의 목적은 quantitative light-induced fluorescence-digital(QLF-D) 시스템을 이용하여 유치와 영구치에 형성된 탈회된 법랑질에 서로 다른 세 종류의 항우식 제품 적용 후 각각의 재광화 효과를 비교하는 데 있다. 연구를 위해 각 48개의 건전한 유치 및 영구치를 대상으로 대조군(1군), 불소 함유 치약(2군), functionalized tricalcium phosphate(fTCP) + 불소 함유 치약(3군), casein phosphopeptide-amorphous calcium phosphate(CPP-ACP) 함유 치아 크림(4군)으로 무작위 분류하였다. 유치 및 영구치에 법랑질 탈회를 유발한 후, 14일 동안 1일 2회 항우식 제품을 처리하였으며, quantitative light-induced fluorescence(QLF)를 이용하여 재광화 효과를 비교 분석하였다. 연구 결과, 세 종류의 항우식 제품 모두 유치와 영구치에서 대조군인 1군에 비해 우식 병소의 무기질 소실량을 유의하게 감소시켰으며, 치약 제품 간 비교에서는 3군과 4군에서 2군에 비해 유의하게 높은 재광화 효과를 나타냈다. 이를 통하여 fTCP와 불소 함유 치약 및 CPP-ACP 함유치아 크림이 유치와 영구치 모두에서 우수한 재광화 효과를 보인다는 것과, QLF-D가 초기 우식 병소와 항우식 제제의 재광화 효과를 정량적으로 평가함에 있어 유용한 장비임을 알 수 있다. 그러므로 임상가들은 유치와 영구치에서의 탈회 및 재광화 평가 시 QLF-D 시스템의 임상적 적용을 고려할 수 있을 것이다.

• The Korean Journal of Ceramics
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• 제4권4호
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• pp.336-339
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• 1998

Bioactive titanium metal can be prepared by simple 5M-NaOH treatment and subsuquent heat treatment at $600^{\circ}C$ to form an amorphous sodium titanate on its surface. In the present study, mechanism of apatite formation on the titanium metal was investigated by examining its surface compositional and structural changes in a simulated body fluid. The apatite formation on the metal was found to proceed in the sequence of 1)$Na^+$ ion release from the sodium titanate to form hydrated titania abundant in Ti-OH groups, 2) early and selective binding of calcium ions with the Ti-OH groups to form a calcium titanate, and 3) late binding of phosphate ions to make apatite nucleation and growth. This indicates that Ti-OH groups do not directly induce the apatite nucleation, but via formation of a calcium titanate.

• 공업화학
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• 제18권3호
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• pp.262-266
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• 2007

연구에서는 칼슘포스페이트(CP) 박막형성에 있어서 마그네슘 이온의 존재가 박막의 물리화학적 그리고 생물학적 특성에 미치는 영향에 관한 연구를 수행하였다. 실험에서는 5 종류의 다른 표면을 사용하였으며, 배양접시(CTL)와 마그네슘이 존재하지 않는 상태에서 제조한 CP박막(CaP)을 비교군으로 사용하였다. 나머지 3개 종류의 박막은 마그네슘 농도가 다른 조건에서 형성하여 사용하였다. 마그네슘의 농도 0.1, 1 그리고 10 mM 조건에서 형성된 박막을 각각 CaPL, CaPM, 그리고 CaPH로 지정하였다. 제조된 CP박막들의 표면형태를 scanning electron microscopy (SEM)으로 관찰한 결과, 마그네슘의 존재가 박막의 다공성을 감소시키는 등의 상당한 영향을 미치는 것으로 나타났다. 또한 CP박막의 결정성을 분석하기 위해 X-ray diffraction (XRD)로 분석한 결과, 제조된 박막들은 무결정성 구조를 갖는 것으로 나타났다. X-ray photoelectron spectroscopy (XPS) 분석을 통해 형성된 박막은 칼슘, 인, 그리고 마그네슘으로 구성되어 있음을 확인하였다. 제조된 박막에 대한 세포부착실험에서 사용한 마그네슘의 농도가 높을수록 세포부착이 감소하는 것으로 나타났다. 그러나 마그네슘 농도증가에 따라 세포증식이 증가하는 것으로 나타났다. 따라서 이러한 결과는 마그네슘이 존재 하에 CP박막의 생체적합성이 향상될 수 있음을 제시한다.