Osteoclastic resorption of calcium phosphate ceramics with different hydroxyapatite/β-tricalcium phosphate ratios

Biomaterials ◽  
1997 ◽  
Vol 18 (15) ◽  
pp. 1037-1041 ◽  
Author(s):  
S Yamada
Keyword(s):  
Calcium Phosphate ◽  
Tricalcium Phosphate ◽  
Calcium Phosphate Ceramics ◽  
Osteoclastic Resorption

Bimodal Porous Bi-Phasic Calcium Phosphate Ceramics and Its Dissolution in SBF Solution

2007 ◽  
Vol 330-332 ◽  
pp. 91-94 ◽  
Author(s):  
Y. Zhang ◽  
Yoshiyuki Yokogawa ◽  
Tetsuya Kameyama
Keyword(s):  
Calcium Phosphate ◽  
Tricalcium Phosphate ◽  
Biphasic Calcium Phosphate ◽  
Reaction Rate ◽  
Ceramic Materials ◽  
Calcium Phosphate Ceramics ◽  
Fine Powders ◽  
Beta Tricalcium Phosphate ◽  
Sbf Solution ◽  
New Phase

Biphasic calcium phosphate (BCP) ceramics, a mixture of hydroxyapatite (HAp) and beta-tricalcium phosphate (β-TCP), of varying HAp/β-TCP ratios were prepared from fine powders. Porous BCP ceramic materials with HAp/β-TCP weight rations of 20/80, 40/60, and 80/20 were prepared. In this study, the bioactivity is reduced at a larger HAp content rate, which is likely related to the high driving pore for the formation of a new phase, and the reaction rate was proportional to the β-TCP. The porous BCP ceramics having a bigger porosity rate can easily under up dissolution. The powder having a larger β-TCP content rate can easily generate a new phase. The dissolution results confirmed that the biodegradation of calcium phosphate ceramics could be controlled by simply adjusting the amount of HAp or β-TCP in the ceramics and porosity rate.

Effect of Macrophage on Degradation of β-TCP Ceramics

2005 ◽  
Vol 288-289 ◽  
pp. 549-552
Author(s):  
Shi Pu Li ◽  
Hong Lian Dai ◽  
Yu Hua Yan ◽  
Xian Ying Cao ◽  
Qi Xin Zheng
Keyword(s):  
Calcium Phosphate ◽  
Carbonic Anhydrase ◽  
Tricalcium Phosphate ◽  
Culture Medium ◽  
Calcium Phosphate Ceramics ◽  
Sem Observation ◽  
Ph Values ◽  
Calcium And Phosphorus

Mice macrophages which were mixed with β-tricalcium phosphate (β-TCP) ceramics powder were cultured, both calcium and phosphorus concentrations in the culture medium were evidently higher than that of β-TCP ceramics powder without cells. The microscope and SEM observation showed that macrophages wrapped β-TCP particles, and then phagocytized them into cytoplasm. The pH values inside and outside macrophage in β-TCP-bearing were tested. The histochemistry observation showed that there were many carbonic anhydrase positive grains in the cytochylema of macroghage after β-TCP ceramics powder being implanted. TEM investigation indicated that many β-TCP particles were phagocytized into the cytochylema of macroghage, and then vacuole was found after particles had degraded. The results showed that macrophages could take part in the degradation of calcium phosphate ceramics in two different ways.

Fabrication of Biphasic Calcium Phosphate Bioceramics from the Recycling of Bone Ash

2012 ◽  
Vol 610-613 ◽  
pp. 2328-2331 ◽  
Author(s):  
Nan Hee Lee ◽  
Kyu Hong Hwang ◽  
Jong Kook Lee
Keyword(s):  
Calcium Phosphate ◽  
Tricalcium Phosphate ◽  
Biphasic Calcium Phosphate ◽  
Raw Materials ◽  
Liquid Environment ◽  
Bone China ◽  
Calcium Phosphate Ceramics ◽  
Bone Ash ◽  
Naoh Solution ◽  
Moisture Protection

Biphasic calcium phosphate bioceramics were fabricated from the recycling of bone ash which is mostly used as raw materials of bone china. Precursor calcium phosphate powders were prepared by soaking the commercial bone ash in 0.1 M of NaOH solution at 80°C for 4 h. Calcium phosphate powders was obtained by calcination at 800°C for 1 h to completely remove residual organics. Biphasic calcium phosphate bioceramics which is composed of hydroxyapatite and tricalcium phosphate was fabricated by the sintering of pressed compacts at 1200°C for 1 h under moisture protection. The bone ash derived-biphasic calcium phosphate ceramics consists of mostly HA and small amounts of α-tricalcium phosphate, magnesium oxide and calcium oxide. After polishing the HA ceramics, they were immersed in buffered water at 37°C for 3 and 7 days. The bone ash derived- biphasic calcium phosphate ceramics show high biostability in liquid environment with immersion time compared with commercial calcium phosphate ceramics.

Zinc-Containing Calcium Phosphate Ceramics with a (Ca+Zn)/P Molar Ratio of 1.67

2005 ◽  
Vol 284-286 ◽  
pp. 31-34 ◽  
Author(s):  
Yu Sogo ◽  
Atsuo Ito ◽  
Koshiro Fukasawa ◽  
Tokoha Sakurai ◽  
Noboru Ichinose ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Tricalcium Phosphate ◽  
Zinc Content ◽  
Molar Ratio ◽  
Necessary Condition ◽  
Calcium Phosphate Ceramics ◽  
Activity Product ◽  
Tcp Phases ◽  
Ion Activity ◽  
Zinc Release

Zinc-containing calcium phosphate ceramics with a (Ca+Zn)/P molar ratio of 1.67 (ZnHAP ceramics) were synthesized to clarify the main phase for zinc release. ZnHAP ceramics with a zinc content at or more than 0.20 wt% contained zinc-containing tricalcium phosphate. The ion activity product of monophasic ZnHAP ceramic containing at or less than 0.13 wt% of zinc corresponded to that of pure HAP ceramic. The presence of tricalcium phosphate (TCP) phases was necessary condition for ZnHAP ceramics to release zinc. The coexistence of TCP phases in the ZnHAP ceramics meant that a phase with a (Ca+Zn)/P molar ratio higher than 1.67 also coexisted. Although the phase was assumed to be zinc oxide, zinc was not concentrated anywhere in the ZnHAP ceramics including grain boundaries.

Cytotoxicity of Various Calcium Phosphate Ceramics

2006 ◽  
Vol 309-311 ◽  
pp. 263-266 ◽  
Author(s):  
Masato Tamai ◽  
Ryusuke Nakaoka ◽  
Toshie Tsuchiya
Keyword(s):  
Calcium Phosphate ◽  
Tricalcium Phosphate ◽  
Calcium Phosphates ◽  
Chinese Hamster ◽  
Lung Fibroblasts ◽  
Cytotoxicity Test ◽  
Tetracalcium Phosphate ◽  
Calcium Phosphate Ceramics ◽  
Fluorine Ions ◽  
Hydrolysis Of

The cytotoxicity of five calcium phosphate ceramics, hydroxyapatite (HAp), flouroapatite (FAp), α-tricalcium phosphate (α-TCP), β-tricalcium phosphate (β-TCP) and tetracalcium phosphate (TTCP), was investigated. Based on the guidelines of biological test for medical devices in Japan, a cytotoxicity test of these calcium phosphates was carried out using Chinese hamster V79 lung fibroblasts. The cytotoxic study revealed that FAp and α-TCP showed high cytotoxicities. From various analyses, it was considered that the cytotoxicity of the FAp was due to fluorine ions extracted in a culture medium and the cytotoxicity of α-TCP resulted from a decrease in pH of the medium by the phosphoric acid, which produced by hydrolysis of( the α-TCP.

Effect of Sintering Temperature on Zinc Substituted Calcium Phosphate Ceramics

2017 ◽  
Vol 890 ◽  
pp. 209-212
Author(s):  
C.M. Mardziah ◽  
Mohamad Firdaus Abdul Wahid ◽  
Koay Mei Hyie ◽  
Nik Rozlin Nik Masdek ◽  
Z. Salleh
Keyword(s):  
Particle Size ◽  
Calcium Phosphate ◽  
Tricalcium Phosphate ◽  
Sintering Temperature ◽  
Calcium Phosphates ◽  
Precipitation Method ◽  
Zinc Ions ◽  
Major Phase ◽  
Calcium Phosphate Ceramics ◽  
Hydroxyapatite Phase

Calcium phosphate ceramics were substituted with several concentrations of zinc ions (0, 5, 10 and 15 mol%) using precipitation method. The effect of sintering temperature at 900 and 1000°C on zinc substituted calcium phosphate ceramics were observed. By increasing the sintering temperature, XRD peaks for zinc substituted calcium phosphate ceramics changed significantly. At sintering temperature of 900°C, hydroxyapatite phase was the major phase in the calcium phosphates containing 0 and 5 mol% zinc. However, at the sintering temperature of 1000°C, hydroxyapatite phase was partly transformed to another phase which was tricalcium phosphate. FESEM observations at sintering temperature of 1000°C exhibit that the particle size of the samples increased with addition of more zinc ions.

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