scholarly journals Fabrication of octacalcium phosphate foams with suitable mechanical strength for use as a bone substitute based on the setting reaction of acidic calcium phosphate granules

2020 ◽  
Vol 128 (11) ◽  
pp. 962-969
Author(s):  
Yuki SUGIURA ◽  
Asuka OONO ◽  
Yoji MAKITA
Keyword(s):  
Calcium Phosphate ◽  
Mechanical Strength ◽  
Bone Substitute ◽  
Octacalcium Phosphate ◽  
Setting Reaction

Preparation of Porous α-TCP Block by Fusion of DCPD Coated α-TCP Spheres

2016 ◽  
Vol 696 ◽  
pp. 57-59
Author(s):  
Tya Indah Arifta ◽  
Melvin L. Munar ◽  
Kanji Tsuru ◽  
Kunio Ishikawa
Keyword(s):  
Calcium Phosphate ◽  
Mechanical Strength ◽  
Bone Substitute ◽  
Single Phase ◽  
Xrd Analysis ◽  
Phosphate Solution ◽  
Carbonate Apatite ◽  
Dicalcium Phosphate Dihydrate ◽  
Phosphate Dihydrate ◽  
Porous Block

The aim of present study was to fabricate porous a-tricalcium phosphate (a-TCP) with adequate mechanical strength and pore interconnectivity. First step, a-TCP spheres were exposed to acidic calcium phosphate solution to allow growth and interlocking of dicalcium phosphate dihydrate (DCPD) crystals precipitated on the surface of the a-TCP spheres. Then, the DCPD-coated a-TCP spheres were sintered at 1,500°C for 6h, which resulted in the fusion of spheres to form the interconnected porous block. XRD analysis showed single phase a-TCP was obtained. Mechanical strength of porous a-TCP was 6.9 ± 1.6 MPa and porosity was 53 ± 5%. The obtained porous a-TCP could be employed as potential bone substitute or precursor for other bioceramics like carbonate apatite and hydroxyapatite.

The Influence of Three Additives on the Setting Reaction Kinetics and Mechanical Strength Evolution of [Alpha]-Tricalcium Phosphate Cements

2011 ◽  
Vol 493-494 ◽  
pp. 397-402
Author(s):  
H.A.I. Cardoso ◽  
M. Motisuke ◽  
Cecília A.C. Zavaglia
Keyword(s):  
Calcium Phosphate ◽  
Mechanical Strength ◽  
Reaction Kinetics ◽  
Tricalcium Phosphate ◽  
Hydrogen Phosphate ◽  
Disodium Hydrogen Phosphate ◽  
Setting Reaction ◽  
Calcium Phosphate Cements ◽  
Strength Evolution ◽  
Low Load

Among the calcium phosphate cements, the system based on alpha-tricalcium phosphate (α-TCP) combines several interesting properties. However, these cements have their use limited to low load applications. The main objective of this study is to evaluate the influence of three different additives on the setting reaction kinetics and mechanical strength evolution of calcium phosphate cements as a function of time. The cement was obtained by mixing α-TCP powder with four different aqueous solutions containing or not containing disodium hydrogen phosphate (Na2HPO4), citric acid (C6H8O7) and/or tannic acid (C76H52O46). It was observed that two cement samples, one of them containing Na2HPO4 and C6H8O7 and another containingNa2HPO4 and C76H52O46 in the liquid phase, presented faster setting reaction and higher mechanical properties. These cements are more suitable for application as bone cement.

Differences of Bone Regeneration by Various Calcium Phosphate/Collagen Composites

2007 ◽  
Vol 361-363 ◽  
pp. 1229-1232 ◽  
Author(s):  
Shinji Kamakura ◽  
Kazuo Sasaki ◽  
Yoshitomo Honda ◽  
Taisuke Masuda ◽  
Takahisa Anada ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Bone Regeneration ◽  
Cross Sections ◽  
Bone Substitute ◽  
Octacalcium Phosphate ◽  
Radiographic Examination ◽  
Synthetic Bone ◽  
Synthetic Bone Substitute ◽  
The Difference ◽  
Made In

Our previous studies showed that synthetic octacalcium phosphate (OCP) enhances bone regeneration more than hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP). Also, a synthetic bone substitute constructed of synthetic octacalcium phosphate (OCP) and porcine atelocollagen sponge (OCP/Col) showed stable bone regeneration. The present study was designed to investigate the difference of bone regeneration by OCP/Col and other calcium phosphate-collagen composites. OCP/Col, β-TCP$-collagen% composite (β-TCP/Col), or HA$-collagen% composite (HA/Col) sponge was prepared from pepsin-digested atelocollagen isolated from the porcine dermis and OCP, β-TCP, or HA granules, respectively. A standardized critical-sized defect was made in the rat calvarium, and various calcium phosphate-collagen composites were implanted into the defect. The rats were fixed at four weeks after implantation and radiographic and histological examinations were performed by undecalcified cross sections of implants. Radiographic examination showed that uniform radiopaque masses were observed in the created defects treated with OCP/Col, whereas granulous and foggy radiopacity was observed in β-TCP/Col and HA/Col. Histological examination showed that newly formed bone was observed in the reticulum of OCP/Col and around the implanted OCP. The regenerated bone by β-TCP/Col or HA/Col seemed to be less than that by OCP/Col and would not to be nucleated by the granules of β-TCP or HA. The present study indicated that bone regeneration by OCP/Col was different from those of β-TCP/Col and HA/Col. Application of OCP/Col would be expected for clinical use in the future.

Fabrication of Apatite Monolith from Calcium Sulphate

2005 ◽  
Vol 288-289 ◽  
pp. 533-536 ◽  
Author(s):  
Ishikawa Kunio ◽  
Shigeki Matsuya ◽  
Yumiko Suzuki ◽  
Koh-ichi Udoh ◽  
Masaharu Nakagawa ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Mechanical Strength ◽  
Present Method ◽  
Calcium Sulfate ◽  
Ammonium Phosphate ◽  
Calcium Sulphate ◽  
Phosphate Solution ◽  
Carbonate Apatite ◽  
Setting Reaction ◽  
Low Crystallinity

Present study evaluated the feasibility of apatite monolith preparation from calcium sulfate monolith using ammonium phosphate solution. We found that calcium phosphate monolith transforms to apatitic monolith without changing its original morphology when a proper temperature and a proper phosphate solution was selected. Prepared apatite was B-type carbonate apatite with low crystallinity. Although mechanical strength of the apatite monolith was lower than original calcium sulphate monolith, we concluded present method may be useful for the fabrication of apatite monolith since we can prepare different shape of apatite monoliths based on the setting reaction of calcium sulphate and compositional transformation to apatitic mineral.

Production and Characterisation of a Collagen-Calcium Phosphate Composite for Use as a Bone Substitute

1998 ◽  
Vol 550 ◽  
Author(s):  
A.C. Lawson ◽  
J.T. Czernuszka
Keyword(s):  
Calcium Phosphate ◽  
Bone Substitute ◽  
Collagen Matrix ◽  
Octacalcium Phosphate ◽  
Entire Cross Section ◽  
Phosphate Ions ◽  
Precipitation Ph ◽  
Composite Microstructure ◽  
Composite Stiffness ◽  
Calcium Phosphate Precipitation

AbstractA composite for use as a bone substitute has been produced by the precipitation of calcium phosphate onto a collagen matrix. A collagen sheet is used as a membrane separating reservoirs of calcium and phosphate ions. The ions diffuse through the membrane and calcium phosphate precipitation occurs on and within the collagen matrix.Composites containing octacalcium phosphate or hydroxyapatite have been produced by varying the precipitation pH. If the correct balance of phosphate and calcium ion concentrations is achieved, precipitation occurs through the entire cross-section of the collagen sheet, giving a composite microstructure analogous to bone. The composite stiffness increases with increasing mineral content, reaching 2.8 GPa with 39 wt % mineral, when measured dry.

Preparation and Characterization of Modified Biphasic Calcium Phosphate Ceramics

2012 ◽  
Vol 506 ◽  
pp. 74-77 ◽  
Author(s):  
Naruporn Monmaturapoj ◽  
Witoon Thepsuwan
Keyword(s):  
Thermal Stability ◽  
Calcium Phosphate ◽  
Flexural Strength ◽  
Mechanical Strength ◽  
Bone Substitute ◽  
Biomedical Applications ◽  
Biphasic Calcium Phosphate ◽  
Bending Strength ◽  
Thermal Stability Of

Biphasic calcium phosphate (BCP) ceramic is commonly used in the biomedical applications particularly as a bone substitute due to its biocompatibility and directly bond to bones. However, the mechanical strength is quite poor. Therefore, well known biocompatible and strong ceramics such as SiO2, ZrO2 and TiO2 were added to improve the strength of BCP. BCP powder with HA/TCP ratios of 70/30 (HAP7030) was obtained by controlling the calcining temperature of the mixture between a pure HA and TCP. SiO2, ZrO2 and TiO2 powder with 2, 5 and 10 %wt were mixed with the HAP7030 powder by ball milling in ethanol. The mixtures were dried, pressed and sintered at 1100°C for 2 hrs. XRD and SEM were used to determine crystal structures and morphology of the sintered samples, respectively. Physical properties and flexural strength of samples were measured. Results showed that the bending strength of HAP7030 sample was rather improved by adding TiO2 than the addition of SiO2 or ZrO2. With increasing TiO2, HAP7030 strength was superior and HAP7030 with 10 %wt of TiO2 obtained the optimum bending strength around 61 MPa. However, the addition of TiO2 induced the thermal stability of HA/TCP, in which HA completely decomposed to β-TCP in this study.

scholarly journals Enhanced Osteogenesis of Dental Pulp Stem Cells In Vitro Induced by Chitosan–PEG-Incorporated Calcium Phosphate Cement

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2252
Author(s):  
Jae Eun Kim ◽  
Sangbae Park ◽  
Woong-Sup Lee ◽  
Jinsub Han ◽  
Jae Woon Lim ◽  
...  
Keyword(s):  
Stem Cells ◽  
Calcium Phosphate ◽  
Zeta Potential ◽  
Mechanical Strength ◽  
Calcium Phosphate Cement ◽  
Dental Pulp ◽  
Dental Pulp Stem Cells ◽  
Ion Trapping ◽  
Alizarin Red

The use of bone graft materials is required for the treatment of bone defects damaged beyond the critical defect; therefore, injectable calcium phosphate cement (CPC) is actively used after surgery. The application of various polymers to improve injectability, mechanical strength, and biological function of injection-type CPC is encouraged. We previously developed a chitosan–PEG conjugate (CS/PEG) by a sulfur (VI) fluoride exchange reaction, and the resulting chitosan derivative showed high solubility at a neutral pH. We have demonstrated the CPC incorporated with a poly (ethylene glycol) (PEG)-grafted chitosan (CS/PEG) and developed CS/PEG CPC. The characterization of CS/PEG CPC was conducted using Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The initial properties of CS/PEG CPCs, such as the pH, porosity, mechanical strength, zeta potential, and in vitro biocompatibility using the WST-1 assay, were also investigated. Moreover, osteocompatibility of CS/PEG CPCs was carried out via Alizarin Red S staining, immunocytochemistry, and Western blot analysis. CS/PEG CPC has enhanced mechanical strength compared to CPC, and the cohesion test also demonstrated in vivo stability. Furthermore, we determined whether CS/PEG CPC is a suitable candidate for promoting the osteogenic ability of Dental Pulp Stem Cells (DPSC). The elution of CS/PEG CPC entraps more calcium ion than CPC, as confirmed through the zeta potential test. Accordingly, the ion trapping effect of CS/PEG is considered to have played a role in promoting osteogenic differentiation of DPSCs. The results strongly suggested that CS/PEG could be used as suitable additives for improving osteogenic induction of bone substitute materials.

scholarly journals Microwave-Assisted Fabrication of Mesoporous Silica-Calcium Phosphate Composites for Dental Application

Polymers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 53
Author(s):  
Adrian Szewczyk ◽  
Adrianna Skwira ◽  
Marta Ginter ◽  
Donata Tajer ◽  
Magdalena Prokopowicz
Keyword(s):  
Calcium Phosphate ◽  
Mesoporous Silica ◽  
Octacalcium Phosphate ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Coating Solution ◽  
X Ray ◽  
Microwave Assisted ◽  
Calcium Orthophosphates ◽  
Different Types

Herein, the microwave-assisted wet precipitation method was used to obtain materials consisting of mesoporous silica (SBA-15) and calcium orthophosphates (CaP). Composites were prepared through immersion of mesoporous silica in different calcification coating solutions and then exposed to microwave radiation. The composites were characterized in terms of molecular structure, crystallinity, morphology, chemical composition, and mineralization potential by Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), and scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM-EDX). The application of microwave irradiation resulted in the formation of different types of calcium orthophosphates such as calcium deficient hydroxyapatite (CDHA), octacalcium phosphate (OCP), and amorphous calcium phosphate (ACP) on the SBA-15 surface, depending on the type of coating solution. The composites for which the progressive formation of hydroxyapatite during incubation in simulated body fluid was observed were further used in the production of final pharmaceutical forms: membranes, granules, and pellets. All of the obtained pharmaceutical forms preserved mineralization properties.

Setting Reaction and Hardening of an Apatitic Calcium Phosphate Cement

1997 ◽  
Vol 76 (4) ◽  
pp. 905-912 ◽  
Author(s):  
M.P. Ginebra ◽  
E. Fernández ◽  
E.A.P. De Maeyer ◽  
R.M.H. Verbeeck ◽  
M.G. Boltong ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Calcium Phosphate Cement ◽  
Setting Reaction
Sign in / Sign up

Export Citation Format

Share Document