Cytotoxicity of Various Calcium Phosphate Ceramics

2006 ◽  
Vol 309-311 ◽  
pp. 263-266 ◽  
Author(s):  
Masato Tamai ◽  
Ryusuke Nakaoka ◽  
Toshie Tsuchiya

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.

2017 ◽  
Vol 890 ◽  
pp. 209-212
Author(s):  
C.M. Mardziah ◽  
Mohamad Firdaus Abdul Wahid ◽  
Koay Mei Hyie ◽  
Nik Rozlin Nik Masdek ◽  
Z. Salleh

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.


1991 ◽  
Vol 252 ◽  
Author(s):  
C. M. Cotell ◽  
D. B. Chrisey ◽  
K. S. Grabowski

ABSTRACTCalcium phosphate-based ceramics were deposited on Ti, Ti-6Al-4V and Si substrates by pulsed laser deposition. The calcium phosphate phase (amorphous, α- or β-tricalciumn phosphate, tetracalcium phosphate, or hydroxylapatite), Ca/P ratio and surface morphology of the films were related to deposition conditions. At substrate temperatures <400°C, films were amorphous. Above 400°C, the gaseous environment during deposition determined the crystalline phase of the films. In O2, deposition of α-tricalcium phosphate was favored between 400 and 700°C and β-tricalcium phosphate was favored above 700°C. Films deposited in low pressures of O2 (<0.05 Torr) were P-deficient. The correct stoichiometry was approached as the pressure of O2 in the chamber during deposition increased. In water vapor-enriched inert gas environments, deposition of hydroxylapatite was observed at temperatures between 400 and 700°C and tetracalcium phosphate was observed at temperatures above 700°C. The surface morphology of hydroxylapatite films depended on the temperature of deposition. Surfaces deposited at higher substrate temperatures showed more recrystallization than those deposited at lower substrate temperatures.


Materials ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1955
Author(s):  
Siri Paulo ◽  
Mafalda Laranjo ◽  
Anabela Paula ◽  
Ana Margarida Abrantes ◽  
João Martins ◽  
...  

Bisphosphonate-associated osteonecrosis of the jaw (BRONJ), a post-surgical non-healing wound condition, is one of the most common side effects in patients treated with nitrogen-containing bisphosphonates. Its physiopathology has been related with suppression of bone turnover, of soft tissue healing and infection. Biphasic calcium phosphates (BCP) are used as a drug delivery vehicle and as a bone substitute in surgical wounds. Due to their capacity to adsorb zoledronate, it was hypothesized these compounds might have a protective effect on the soft tissues in BRONJ wounds. To address this hypothesis, a reproducible in vivo model of BRONJ in Wistar rats was used. This model directly relates chronic bisphosphonate administration with the development of osteonecrosis of the jaw after tooth extraction. BCP granules were placed in the alveolus immediately after tooth extraction in the test group. The animals were evaluated through nuclear medicine, radiology, macroscopic observation, and histologic analysis. Encouragingly, calcium phosphate ceramics were able to limit zoledronate toxicity in vivo and to favor healing, which was evidenced by medical imaging (nuclear medicine and radiology), macroscopically, and through histology. The studied therapeutic option presented itself as a potential solution to prevent the development of maxillary osteonecrosis.


2007 ◽  
Vol 561-565 ◽  
pp. 1553-1556 ◽  
Author(s):  
Sen Yang ◽  
Hau Chung Man

A layer of bioceramic HA was coated on laser gas nitrided and grit-blasted pure Ti substrates using plasma-spraying technique, respectively. X-ray diffraction analysis showed that the microstructures of the coating were mainly composed of HA, amorphous calcium phosphate and some minute phases of tricalcium phosphate, tetracalcium phosphate and calcium oxide. The experimental results showed that the 3-D TiN dendritic scaffold structure produced on the surface of pure Ti using laser gas nitriding technique in advance could anchor the HA coating and improved the interfacial adherence significantly as compared with those on the grit blasted surfaces.


2007 ◽  
Vol 330-332 ◽  
pp. 91-94 ◽  
Author(s):  
Y. Zhang ◽  
Yoshiyuki Yokogawa ◽  
Tetsuya Kameyama

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.


2005 ◽  
Vol 288-289 ◽  
pp. 549-552
Author(s):  
Shi Pu Li ◽  
Hong Lian Dai ◽  
Yu Hua Yan ◽  
Xian Ying Cao ◽  
Qi Xin Zheng

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.


2005 ◽  
Vol 04 (04) ◽  
pp. 517-523
Author(s):  
WENJIAN WENG ◽  
YANBO GAO ◽  
LILI PAN ◽  
YANBAO LI ◽  
PIYI DU ◽  
...  

Biodegradable porous materials can serve as a scaffold in tissue engineering. In this work, highly porous nano-calcium phosphate (NCP)/poly(L-lactic acid)(PLLA) composites were prepared by a thermally induced phase separation technique. Five calcium phosphates with different biodegradation rate were selected, i.e. amorphous calcium phosphate, α-tricalcium phosphate, β-tricalcium phosphate and biphasic α/β-tricalcium phosphate. The results showed that the NCP particles could be homogenously incorporated into pore walls; the composites had a porosity of ~90%, and a pore size of ~200 μm. From the point of view of materials science, the obtained porous NCP/PLLA composites demonstrate to have a capability of applying in bone tissue engineering.


2012 ◽  
Vol 610-613 ◽  
pp. 2328-2331 ◽  
Author(s):  
Nan Hee Lee ◽  
Kyu Hong Hwang ◽  
Jong Kook Lee

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.


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