Fabrication of three-dimensional interconnected porous blocks composed of robust carbonate apatite frameworks

2020 ◽  
Vol 46 (12) ◽  
pp. 20045-20049
Author(s):  
Tansza S. Putri ◽  
Koichiro Hayashi ◽  
Kunio Ishikawa
Keyword(s):  
Three Dimensional ◽  
Carbonate Apatite ◽  
Porous Blocks

Osteoconductivity and Bioresorption of an Interconnecting Porous Carbonate Apatite with Enhanced Mechanical Strength

2016 ◽  
Vol 696 ◽  
pp. 23-26
Author(s):  
Nguyen Xuan Thanh Tram ◽  
Michito Maruta ◽  
Kanji Tsuru ◽  
Shigeki Matsuya ◽  
Kunio Ishikawa
Keyword(s):  
Mechanical Strength ◽  
Histological Analysis ◽  
Three Dimensional ◽  
Hydrothermal Condition ◽  
Carbonate Apatite ◽  
Ct Scanner ◽  
Micro Computed Tomography ◽  
Bone Substitute Material ◽  
Japanese Male

We have established a processing method to fabricate three - dimensional porous carbonate apatite (CO3Ap) with interconnected porous structure and improved mechanical strength. Briefly, porous CO3Ap materials were produced via phosphorization of porous calcite precursor in hydrothermal condition. In order to make porous calcite precursor, negative replication of modified polyurethane foam template was conducted. In this study, an in vivo behavior of that porous CO3Ap was evaluated. The interconnected porous CO3Ap material was implanted in the tibia of Japanese male rabbits and removed after a period of 6 months. Micro-computed tomography (μ-CT) scanner and histological analysis were used to characterize the bone formation response of the porous CO3Ap. The results suggest that porous CO3Ap with enhanced mechanical strength was not only osteoconductive but also bioresorbable therefore it could be used as bone substitute material.

Fabrication of Calcite Foam by Inverse Ceramic Foam Method

2012 ◽  
Vol 529-530 ◽  
pp. 153-156 ◽  
Author(s):  
Tram Nguyen Xuan Thanh ◽  
Michito Maruta ◽  
Kanji Tsuru ◽  
Alireza Valanezhad ◽  
Shigeki Matsuya ◽  
...  
Keyword(s):  
Mechanical Strength ◽  
Porous Structure ◽  
Polyurethane Foam ◽  
Ceramic Powder ◽  
Three Dimensional ◽  
Ceramic Foam ◽  
Carbonate Apatite ◽  
High Porosity ◽  
Synthetic Resin ◽  
Polyurethane Sponge

We have previously reported that calcite foam that had interconnected porous structure could be prepared by ceramic foam method and it transformed to carbonate apatite (CO3Ap). In the ceramic foam method, polyurethane sponge was used as a template. The polyurethane sponge was immersed in the ceramics slurry, and the strut of the polyurethane foam was covered by ceramic powder. After that it was dried and sintered at high temperature. Calcite foams produced by this approach were comprised of a three-dimensional (3D) interconnected porous structure that facilitated cell penetration. However, all foams have a common limitation: the inherent lack of mechanical strength associated with high porosity. Therefore, in this study, an inverse ceramic foam method was studied; multi polyurethane coating method using polyurethane foam as a template. In this study, the compressive strength was improved by an inverse replication allowed for decreasing porosity while at the same time maintaining the interconnectivity. The burnable synthetic resin coating layer was introduced onto struts of polyurethane foam to make the triangular struts become more round and thick, consequently producing large round capillary within the foam structure fulfilling the requirement for osteoblast colonization. In particular, polyurethane foam was dipped orderly into two monomers, followed by centrifugation to remove excess liquids inside foam. After resin curing, a layer of synthetic resin was coated strut of foam. Calcium hydroxide Ca (OH)2 slurry was then infiltrated into resin coated-polyurethane foam. By firing at 600°C in O2-CO2 stream, polyurethane template was burnt off and Ca (OH)2 was converted into calcite. Negative replicated calcite foam was fabricated and characterized micro-structurally with interconnectivity and improved mechanical strength. The results obtained in this study suggested that this method dramatically improved the mechanical strength of the calcite foam without sacrificing the interconnected structure, and this means that the calcite foam obtained in this method could be precursors for the 3D interconnected porous CO3Ap foam.

Use of Low Voltage High Resolution SEM (LVHRSEM) to Reveal Architectural Organization of Bone Mineral

1997 ◽  
Vol 3 (S2) ◽  
pp. 1227-1228
Author(s):  
V. Benezra ◽  
M. Spector ◽  
L.W. Hobbs
Keyword(s):  
Composite Structures ◽  
Low Voltage ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Carbonate Apatite ◽  
Structural Protein ◽  
Apatite Phase ◽  
Organ Systems ◽  
Bone Substitute Materials ◽  
Architectural Organization

Load-bearing tissues in different organ systems display a wide variety of mechanical properties, yet are composed of only a few different molecules, with collagen as the principal structural protein. In bone, a mineral phase comprising carbonate-apatite crystallites confers compressive and torsional strength. The arrangement of collagen and apatite into three-dimensional hierarchical composite structures enables the tissue to bear high loads while maintaining flexibility. Moreover, bone serves as the body’s chemical storehouse for non-collagenous proteins and smaller molecular weight anions and cations such as calcium.An understanding of the three-dimensional structure of the apatite phase at the nanometer and micrometer levels can provide insights into the properties of bone, and serve as the guide for the development of bone substitute materials. Transmission electron microscopy (TEM) has been valuable in revealing certain ultrastructural features of the mineral. However, it has not yet been possible to obtain three-dimensional reconstructions of the morphology and distribution of the apatite phase of bone using this method.

Three-Dimensional Porous Carbonate Apatite with Sufficient Mechanical Strength as a Bone Substitute Material

2014 ◽  
Vol 891-892 ◽  
pp. 1559-1564 ◽  
Author(s):  
Tram Nguyen Xuan Thanh ◽  
Michito Maruta ◽  
Kanji Tsuru ◽  
Shigeki Matsuya ◽  
Kunio Ishikawa
Keyword(s):  
Mechanical Strength ◽  
Polyurethane Foam ◽  
Three Dimensional ◽  
Ceramic Foam ◽  
Chemical Compositions ◽  
Phosphate Solution ◽  
Carbonate Apatite ◽  
Layer By Layer ◽  
Ct Scanner ◽  
Micro Computed Tomography

In this study, three - dimensional porous carbonate apatite (CO3Ap) materials with the chemical compositions and structures similar to cancellous bone were produced via phosphorization of porous calcite precursor in hydrothermal condition. In order to make porous calcite precursor, negative replication of polyurethane foam that named as inverse ceramic foam method was conducted. When the polyurethane template occupied within the ceramic solid walls disappeared due to burning at high temperature, interconnected hollow pathways were produced. Polyurethane foam was used as a porogen - template firstly was coated layer by layer with synthetic resin to modify morphology and enlarge thickness of struts so as to expand porous area for satisficing cellular bioactivities. Calcium hydroxide (Ca(OH)2) slurry was then infiltrated into resin coated-polyurethane foam. Heat treatment in atmosphere of oxygen and carbon dioxide gases was carried out to eliminate polyurethane template and induce carbonation process. Ca(OH)2 was converted to calcite with the internal porous channel architecture simulating polyurethane foam struts network. That interconnected porous calcite was subsequently transformed to CO3Ap with remaining the same macroporous structure through hydrothermal treatment in phosphate solution. The porous CO3Ap materials were implanted in the tibia of Japanese male rabbits and removed after a period of 3 months. The bone formation response of the three - dimensional porous carbonate apatite in vivo has been preliminary studied using micro-computed tomography (µ-CT) scanner. The results showed that the porous implant materials have sufficient mechanical strength to provide structural support during bone remodeling and successfully bond with host bone.

Fabrication of Carbonate Apatite Form and its Basic Properties

2005 ◽  
Vol 284-286 ◽  
pp. 373-376 ◽  
Author(s):  
Ishikawa Kunio ◽  
Koh-ichi Udoh ◽  
Hanae Wakae ◽  
Melvin L. Munar ◽  
Shigeki Matsuya ◽  
...  
Keyword(s):  
Sodium Bicarbonate ◽  
Mechanical Strength ◽  
Hydrothermal Treatment ◽  
Tricalcium Phosphate ◽  
Preparation Method ◽  
Three Dimensional ◽  
Carbonate Apatite ◽  
Powder Suspension ◽  
Interconnected Pore ◽  
The Ideal

Carbonate apatite form that has three-dimensional fully interconnected pore was prepared based on so-called ceramics form preparation method. First, a-tricalcium phosphate (a-TCP) form was prepared by immersing polyurethane form into a-TCP powder suspension. The form was heated in an electronic furnace for sintering a-TCP as well as for burning out of the polyurethane form. Then hydrothermal treatment was preformed at 200 degrees in the presence of saturated sodium bicarbonate for 24 hours. Although the mechanical strength of the carbonate apatite form was poorer when compared with a-TCP form, we found that the hydrothermal treatment of a -TCP form result in the formation of B-type carbonate apatite form without changing the ideal morphology of a -TCP form.

scholarly journals Comparison of the performances of low-crystalline carbonate apatite and Bio-Oss in sinus augmentation using three-dimensional image analysis

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Koudai Nagata ◽  
Kei Fuchigami ◽  
Ryoji Kitami ◽  
Yurie Okuhama ◽  
Kana Wakamori ◽  
...  
Keyword(s):  
Image Analysis ◽  
Bone Resorption ◽  
Bone Graft ◽  
Three Dimensional ◽  
Treated Group ◽  
Carbonate Apatite ◽  
Graft Material ◽  
Sinus Lift ◽  
Bone Graft Material ◽  
Dimensional Image

Abstract Background In locations where the alveolar bone height is low, such as at the maxillary molars, implant placement can be difficult, or even impossible, without procedures aimed at generating new bone, such as sinus lifts. Various types of bone graft materials are used after a sinus lift. In our study, a three-dimensional image analysis using a volume analyzer was performed to measure and compare the volume of demineralized bovine bone mineral (Bio-Oss®) and carbonate apatite (Cytrans®) after a sinus lift, as well as the amount of bone graft material resorption. Patient data were collected from cone-beam computed tomography images taken before, immediately following, and 6 months after the sinus lift. Using these images, both the volume and amount of resorption of each bone graft material were measured using a three-dimensional image analysis system. Results The amount of bone resorption in the Bio-Oss®-treated group was 25.2%, whereas that of the Cytrans®-treated group was 14.2%. A significant difference was found between the two groups (P < 0.001). Conclusions Our findings indicate that the volume of bone resorption was smaller in the Cytrans®-treated group than in the Bio-Oss®-treated group, suggesting that Cytrans® is more promising for successful implant treatments requiring a sinus lift.

The orbit of Pluto over a long interval of time

1966 ◽  
Vol 25 ◽  
pp. 227-229 ◽  
Author(s):  
D. Brouwer
Keyword(s):  
Periodic Orbit ◽  
Numerical Integration ◽  
Restricted Problem ◽  
Three Dimensional ◽  
The Third ◽  
Circular Restricted Problem ◽  
Resonance Relation

The paper presents a summary of the results obtained by C. J. Cohen and E. C. Hubbard, who established by numerical integration that a resonance relation exists between the orbits of Neptune and Pluto. The problem may be explored further by approximating the motion of Pluto by that of a particle with negligible mass in the three-dimensional (circular) restricted problem. The mass of Pluto and the eccentricity of Neptune's orbit are ignored in this approximation. Significant features of the problem appear to be the presence of two critical arguments and the possibility that the orbit may be related to a periodic orbit of the third kind.

Conformation of Ribosomes from Escherichia Coli

1974 ◽  
Vol 32 ◽  
pp. 210-211
Author(s):  
M. Boublik ◽  
W. Hellmann ◽  
F. Jenkins
Keyword(s):  
Binding Sites ◽  
Ribosomal Proteins ◽  
Fluorescent Dyes ◽  
Protein Biosynthesis ◽  
Three Dimensional ◽  
Spatial Arrangement ◽  
Dimensional Structure ◽  
Complete Understanding ◽  
And Function

The present knowledge of the three-dimensional structure of ribosomes is far too limited to enable a complete understanding of the various roles which ribosomes play in protein biosynthesis. The spatial arrangement of proteins and ribonuclec acids in ribosomes can be analysed in many ways. Determination of binding sites for individual proteins on ribonuclec acid and locations of the mutual positions of proteins on the ribosome using labeling with fluorescent dyes, cross-linking reagents, neutron-diffraction or antibodies against ribosomal proteins seem to be most successful approaches. Structure and function of ribosomes can be correlated be depleting the complete ribosomes of some proteins to the functionally inactive core and by subsequent partial reconstitution in order to regain active ribosomal particles.

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