scholarly journals Injectable Enzymatically Hardened Calcium Phosphate Biocement

2020 ◽  
Vol 11 (4) ◽  
pp. 74
Author(s):  
Lubomir Medvecky ◽  
Radoslava Štulajterová ◽  
Maria Giretova ◽  
Lenka Luptakova ◽  
Tibor Sopčák
Keyword(s):  
Compressive Strength ◽  
Calcium Phosphate ◽  
Setting Time ◽  
Microstructural Analysis ◽  
Chemical Properties ◽  
Gene Expressions ◽  
Cement Pastes ◽  
Anionic Polyelectrolyte ◽  
Simple Possibility

(1) Background: The preparation and characterization of novel fully injectable enzymatically hardened tetracalcium phosphate/monetite cements (CXI cements) using phytic acid/phytase (PHYT/F3P) hardening liquid with a small addition of polyacrylic acid/carboxymethyl cellulose anionic polyelectrolyte (PAA/CMC) and enhanced bioactivity. (2) Methods: Composite cements were prepared by mixing of calcium phosphate powder mixture with hardening liquid containing anionic polyelectrolyte. Phase and microstructural analysis, compressive strength, release of ions and in vitro testing were used for the evaluation of cement properties. (3) Results: The simple possibility to control the setting time of self-setting CXI cements was shown (7–28 min) by the change in P/L ratio or PHYT/F3P reaction time. The wet compressive strength of cements (up to 15 MPa) was close to cancellous bone. The increase in PAA content to 1 wt% caused refinement and change in the morphology of hydroxyapatite particles. Cement pastes had a high resistance to wash-out in a short time after cement mixing. The noncytotoxic character of CX cement extracts was verified. Moreover, PHYT supported the formation of Ca deposits, and the additional synergistic effect of PAA and CMC on enhanced ALP activity was found, along with the strong up-regulation of osteogenic gene expressions for osteopontin, osteocalcin and IGF1 growth factor evaluated by the RT-qPCR analysis in osteogenic αMEM 50% CXI extracts. (4) Conclusions: The fully injectable composite calcium phosphate bicements with anionic polyelectrolyte addition showed good mechanical and physico-chemical properties and enhanced osteogenic bioactivity which is a promising assumption for their application in bone defect regeneration.

Improving the anti-washout property of calcium phosphate cement by introducing konjac glucomannan/κ-carrageenan blend

2019 ◽  
Vol 33 (8) ◽  
pp. 1094-1104 ◽  
Author(s):  
Guowen Qian ◽  
Xingmei Li ◽  
Fupo He ◽  
Jiandong Ye
Keyword(s):  
Compressive Strength ◽  
Calcium Phosphate ◽  
Calcium Phosphate Cement ◽  
Setting Time ◽  
Konjac Glucomannan ◽  
Water Soluble ◽  
Mouse Bone Marrow ◽  
Human Cancellous Bone ◽  
Marrow Mesenchymal Stem Cells

Anti-washout calcium phosphate cement (CPC) was prepared by dissolving water-soluble konjac glucomannan (KGM) and κ-carrageenan (KC) blend in the cement liquid. The anti-washout property, setting time, compressive strength and in vitro cytocompatibility of the CPC modified with KGM/KC blend were evaluated. The results indicated that the CPC pastes modified with KGM/KC blend exhibited excellent anti-washout property. The addition of KGM/KC blend shortened the setting time and increased the injectability of CPC. Although the introduction of KGM/KC blend reduced the compressive strength of CPC, the compressive strength still surpassed that of human cancellous bone. The optimal KGM/KC mass ratio was 2:8, with which the modified cement exhibited the most efficient washout resistance and the highest compressive strength. The introduction of KGM/KC blend obviously promoted the proliferation of mouse bone marrow mesenchymal stem cells. This anti-washout CPC modified by KGM/KC blend with excellent in vitro cytocompatibility will have good prospects for application in bone defect repair.

Study on Fast-Releasing Calcium Phosphate Cement for Accelerating the Release of Antibiotic

2011 ◽  
Vol 295-297 ◽  
pp. 189-192
Author(s):  
Mao Hong Li ◽  
Shu Xin Qu ◽  
Ning Yao ◽  
Yu Suo Wang ◽  
Ju Mei Zhao ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Compressive Strength ◽  
Calcium Phosphate ◽  
Calcium Phosphate Cement ◽  
Setting Time ◽  
Clinical Applications ◽  
Soluble Component ◽  
Antibiotic Release ◽  
Soluble Components

The long-retention of antibiotics in Calcium Phosphate Cement (CPC) may induce the development of drug resistance. Fast-releasing CPC containing antibiotics (FRCPC) was proposed as a solution to this problem and studied in this work. The FRCPC containing different proportions of soluble component were prepared and characterized. The setting time, compressive strength, degree of the conversion, in vitro antibiotic release and fracture surface morphology of FRCPC were studied. The results showed that the setting time increased, the compressive strength decreased, the in vitro antibiotic release accelerated with increasing fraction of soluble component in FRCPC. The setting time and compressive strength of FRCPC containing 20 wt% soluble components were close to the requirements of clinical applications, and the in vitro release was completed within 7 d. These results mentioned above showed that the FRCPC with suitable proportions of soluble components may prevent the development of drug resistance and may find applications in clinics.

scholarly journals Calcium Phosphate Cement Modified with Silicon Nitride/Tricalcium Phosphate Microgranules

2020 ◽  
Vol 20 (1) ◽  
pp. 56-75
Author(s):  
Lubomir Medvecky ◽  
Radoslava Stulajterova ◽  
Maria Giretova ◽  
Tibor Sopcak ◽  
Maria Faberova ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Silicon Nitride ◽  
Calcium Phosphate ◽  
Tricalcium Phosphate ◽  
Setting Time ◽  
Controlled Drug Release ◽  
Tetracalcium Phosphate ◽  
Composite Cement ◽  
Highly Porous

Abstract Tetracalcium phosphate/monetite biocement was modified with 10 and 30 wt. % addition of highly porous silicon nitride/α-tricalcium phosphate (αTCP) microgranules with various content of αTCP. A composite cement powder mixture was prepared using mechanical homogenization of basic components. The accelerated release of dexamethasone from composite cement was revealed, which indicates their possible utilization for controlled drug release. The wet compressive strength of cements (<17 MPa) was significantly reduced (more than 30%) in comparison with the unmodified cement and both compressive strength and setting time were influenced by the content of αTCP in microgranules. The addition of microgranules caused a 20% decrease in final cement density. Microgranules with a higher fraction of αTCP showed good in vitro SBF bioactivity with precipitation of hydroxyapatite particles. Microstructure analysis of fractured cements demonstrated excellent interconnection between microgranules and cement calcium phosphate matrix, but also showed lower mechanical strength of microgranule cores.

Physicochemical and Mechanical Properties of Composite of Chitosan Microspheres/Calcium Phosphate Cement

2007 ◽  
Vol 336-338 ◽  
pp. 1654-1657
Author(s):  
Rui Liu ◽  
Li Min Dong ◽  
Qing Feng Zan ◽  
Chen Wang ◽  
Jie Mo Tian
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Calcium Phosphate ◽  
Bone Cement ◽  
Setting Time ◽  
Chemical Properties ◽  
Phase Evolution ◽  
Chitosan Microspheres ◽  
Setting Times ◽  
Calcium Phosphate Bone Cement

The aim of this work is to improve the mechanical properties of calcium phosphate bone cement (CPC) by appending chitosan microspheres to CPC base. That chitosan degrades rapidly than bone cement has been proved by previous investigations. Porous CPC has low compressive strength because of the pores in it weakening the structure. Additive chitosan microspheres can improve the mechanical properties by bearing the compress with the CPC base and produce pores after degradation. This study investigates the effect of chitosan microspheres on the setting time, mechanical properties, phase evolution and morphology of CPC. The additive proportion of chitosan microspheres ranges from 0 wt% to 30 wt%. Compared with original CPC, the modified CPC has higher compressive strength, without significantly affecting the chemical properties. The phase composition of the CPC is tested by XRD. The microstructures of CPC are observed using SEM. The final setting times range from 5~15 minutes and can be modulated by using different liquid and powder (L/P) ratio.

Characterization of α/β-TCP Based Injectable Calcium Phosphate Cement as a Potential Bone Substitute

2012 ◽  
Vol 529-530 ◽  
pp. 157-160 ◽  
Author(s):  
Kemal Sariibrahimoglu ◽  
Joop G.C. Wolke ◽  
Sander C.G. Leeuwenburgh ◽  
John A. Jansen
Keyword(s):  
Compressive Strength ◽  
Calcium Phosphate ◽  
Setting Time ◽  
Surrounding Tissue ◽  
Calcium Phosphate Cements ◽  
Apatite Cement ◽  
Tcp Phase

Calcium phosphate cements (CPCs) can be a suitable scaffold material for bone tissue engineering because of their osteoconductivity and perfect fit with the surrounding tissue when injected in situ. However, the main disadvantage of hydroxyapatite (HA) forming CPC is its slow degradation rate, which hinders complete bone regeneration. A new approach is to use hydraulic apatite cement with mainly α/β-tricalciumphosphate (TCP) instead of α-TCP. After hydrolysis the α/β-TCP transforms in a partially non-absorbable HA and a completely resorbable β-TCP phase. Therefore, α-TCP material was thermally treated at several temperatures and times resulting in different α/β-TCP ratios. In this experiment, we developed and evaluated injectable biphasic calcium phosphate cements (BCPC) in vitro. Biphasic α/β-TCP powder was produced by heating α-TCP ranging from 1000-11250°C. Setting time and compressive strength of the CPCs were analyzed after soaking in PBS for 6 weeks. Results demonstrated that the phase composition can be controlled by the sintering temperature. Heat treatment of α-TCP, resulted in 100%, 75% and 25% of α-to β-TCP transformation, respectively. Incorporation of these sintered BCP powder into the cement formulation increased the setting time of the CPC paste. Compressive strength decreased with increasing β-TCP content. In this study, biphasic CPCs were produced and characterized in vitro. This injectable biphasic CPC presented comparable properties to an apatitic CPC.

scholarly journals Effect of Calcium Nitrate on the Properties of Portland–Limestone Cement-Based Concrete Cured at Low Temperature

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1611
Author(s):  
Gintautas Skripkiūnas ◽  
Asta Kičaitė ◽  
Harald Justnes ◽  
Ina Pundienė
Keyword(s):  
Compressive Strength ◽  
Cement Paste ◽  
Setting Time ◽  
Calcium Nitrate ◽  
Curing Temperature ◽  
Hardened Concrete ◽  
Cement Pastes ◽  
Initial Setting Time ◽  
Initial Setting ◽  
Early Strength

The effect of calcium nitrate (CN) dosages from 0 to 3% (of cement mass) on the properties of fresh cement paste rheology and hardening processes and on the strength of hardened concrete with two types of limestone-blended composite cements (CEM II A-LL 42.5 R and 42.5 N) at different initial (two-day) curing temperatures (−10 °C to +20 °C) is presented. The rheology results showed that a CN dosage up to 1.5% works as a plasticizing admixture, while higher amounts demonstrate the effect of increasing viscosity. At higher CN content, the viscosity growth in normal early strength (N type) cement pastes is much slower than in high early strength (R type) cement pastes. For both cement-type pastes, shortening the initial and final setting times is more effective when using 3% at +5 °C and 0 °C. At these temperatures, the use of 3% CN reduces the initial setting time for high early strength paste by 7.4 and 5.4 times and for normal early strength cement paste by 3.5 and 3.4 times when compared to a CN-free cement paste. The most efficient use of CN is achieved at −5 °C for compressive strength enlargement; a 1% CN dosage ensures the compressive strength of samples at a −5 °C initial curing temperature, with high early strength cement exceeding 3.5 MPa but being less than the required 3.5 MPa in samples with normal early strength cement.

Primary Study of an Injectable In Situ Composite of Collagen/Calcium Phosphate Porous Scaffold for Bone Substitute

2006 ◽  
Vol 309-311 ◽  
pp. 857-860 ◽  
Author(s):  
Q. Yao ◽  
Dong Xiao Li ◽  
K.W. Liu ◽  
Bo Zhang ◽  
H. Li ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Calcium Phosphate ◽  
Ph Value ◽  
Porous Scaffold ◽  
Setting Time ◽  
Primary Study ◽  
In Situ Composite ◽  
Setting Process ◽  
Main Material

This study was to develop an injectable biocompatible and porous calcium phosphate collagen composite cement scaffold by in situ setting. TTCP was prepared as main material of the CPC powder, and the collagen solution was added into the phosphoric acid directly to form the liquid phase. The injectable time (tI), setting time (tS) and setting temperature (TS), along with the PH value were recorded during the setting process. The compressive strength, morphology and porosity were tested. With the increase of collagen, this novel CPC get a tI of 5mins to 8mins, tS of 20mins to 30mins, compressive strength from 1.5MPa to 4MPa, and the porosity from 40% to 60%. This study gave a possibility to form a porous scaffold of collagen/CPC composite with the nature of injectability and setting in situ.

The pH-Dependent Properties of the Biphasic Calcium Phosphate for Bone Cements

2014 ◽  
Vol 21 ◽  
pp. 3-16 ◽  
Author(s):  
Nuan La Ong Srakaew ◽  
Sirirat Tubsungnoen Rattanachan
Keyword(s):  
Compressive Strength ◽  
Liquid Phase ◽  
Calcium Phosphate ◽  
Phase Analysis ◽  
Calcium Phosphate Cement ◽  
Biphasic Calcium Phosphate ◽  
Setting Time ◽  
Bone Cements ◽  
Apatite Formation ◽  
Apatite Cement

Self-setting calcium phosphate cement (CPC) has been used in bone repair and substitution due to their excellent biocompatibility, bioactive as well as simplicity of preparation and use. The inherent brittleness and slow degradation are the major disadvantages for the use of calcium phosphate cements. To improve the degradation for the traditional CPC, the apatite cement formula incorporated with β-tricalcium phosphate (β-TCP) with varying concentration were studied and the effect of the pH value of liquid phase on the properties of this new calcium phosphate cement formula was evaluated. The apatite cements containing β-TCP for 10 and 40 wt.% were mixed into the aqueous solution with different pH values and then aging in absolute humidity at 37°C for 7 days. The setting time and phase analysis of the biphasic calcium phosphate were determined as compared to the apatite cement. For proper medical application, the compressive strength, the phase analysis and the degradation of the CPC samples at pH 7.0 and 7.4 were evaluated after soaking in the simulated body fluid (SBF) at 37°C for 7 days. The results indicated that the properties of the samples such as the setting time, the compressive strength related to the phase analysis of the set cements. The high degradation of the CPC was found in the cement with increasing β-TCP addition due to the phase after setting. Apatite formation with oriented plate-like morphology was also found to be denser on the surface of the biphasic bone cements after soaking in SBF for 7 days. The obtained results indicated that the cement containing β-TCP mixed with the liquid phase at pH 7.4 could be considered as a highly biodegradable and bioactive bone cement, as compared to the traditional CPC.

scholarly journals Brushite cement containing gelatin: evaluation of mechanical strength and in vitro degradation

Cerâmica ◽  
2019 ◽  
Vol 65 (374) ◽  
pp. 261-266 ◽  
Author(s):  
L. P. Silva ◽  
M. D. P. Ribeiro ◽  
E. S. Trichês ◽  
M. Motisuke
Keyword(s):  
Mechanical Properties ◽  
Weight Loss ◽  
Compressive Strength ◽  
Solid Phase ◽  
Setting Time ◽  
Biological Properties ◽  
Solubility In Water ◽  
Ringer’S Solution ◽  
Weight Loss Data

Abstract Calcium phosphate cements (CPCs) are potential materials for repairing bone defects, mainly due to their excellent biocompatibility and osteoconductivity. Nevertheless, their low mechanical properties limit their usage in clinical applications. The gelatin addition may improve the mechanical and biological properties of CPCs, but their solubility in water may increase the porosity of the cement during degradation. Thus, the aim of this work was to investigate the influence of gelatin on the setting time, compressive strength and degradation rate of a brushite cement. CPCs were prepared with the addition of 0, 5, 10 and 20 wt% of gelatin powder in the solid phase of the cement. The results indicated that the setting time increased with gelatin. Furthermore, cement with 20 wt% of gelatin had an initial compressive strength of 14.1±1.8 MPa while cement without gelatin had 4.5±1.2 MPa. The weight loss, morphology and compressive strength were evaluated after degradation in Ringer’s solution. According to the weight loss data, gelatin was eliminated of samples during degradation. It was concluded that the presence of gelatin improved CPCs mechanical properties; however, as degradation in Ringer’s solution evolved, cement compressive strength decreased due to gelatin dissolution and, consequently, an increase in sample porosity.

Biodegradable Bone Cement Using Calcium Phosphate Glass

2006 ◽  
Vol 309-311 ◽  
pp. 861-864 ◽  
Author(s):  
Byung Hyun Lee ◽  
Min Chul Kim ◽  
Kyoung Nam Kim ◽  
Kwang Mahn Kim ◽  
Seong Ho Choi ◽  
...  
Keyword(s):  
Weight Loss ◽  
Compressive Strength ◽  
Calcium Phosphate ◽  
Simulated Body Fluid ◽  
Dissolution Rate ◽  
Phosphate Glass ◽  
Body Fluid ◽  
Setting Time ◽  
Ageing Test ◽  
Dynamic Assay

In preliminary ageing test, the cement using only calcium phosphate glass as power phase cracked with 1 day in simulated body fluid because of high dissolution rate of the cement. We added 30 wt% of either β-TCP or HA to 70 wt% calcium phosphate glass as powder phase to control the dissolution rate of the cement and performed in vitro ageing test in simulated body fluid by dynamic protocol as well as static protocol to confirm the possibility of controlling. Adding either β-TCP or HA to the cement increases the setting time and decreases the compressive strength. In dynamic assay, the pH of extract is maintained over 7. However, pH decreased to around 5 in static assay. Therefore, weight loss by static protocol continuously increased for 14 days, while weight loss by dynamic protocol almost saturated. In XRD patterns of ageing cements, CaO peaks appeared. CaO peak was maximized most lately in dynamic assay of the cement adding HA and within 7 days, the cement adding HA showed higher weight loss. It is indicated that CaO formed in surface of the cement hinder the dissolution of the cement. In addition, compressive strength increased when the CaO peak was maximized.

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