Calcium PHOSPHATE cements (CPCs), using B-TRICALCIUM PHOSPHATE (ß-TCP, Ca3 (P04)2), dicalcium PHOSPHATE (DCP, CaHP04), calcium carbonate (Ca CO3), and hydroxylapatite (HAp, Ca10(P04)6(OH)2) as powder cement and disodium hydrogen PHOSPHATE (Na2HP04) solution as liquid component were prepared. After mixing the powder and liquid constituents, injectable and self-setting calcium PHOSPHATE cements (CPCs) were prepared with different liquid to powder ratios (UP) that formed hydroxylapatite and ß-TRICALCIUM PHOSPHATE as the only end products, which were characterized by FTIR, XRD and SEM techniques. The results showed that, at certain concentration of Na2HP04 (6 wt%), the initial and final setting times decreased by decreasing the UP ratio.

TRICALCIUM PHOSPHATE as hydroxyapatite is used as a suspension stabilizer in styrene polymerization process. Particle size of TCP plays an essential role in the particles’ size distribution and geometrical form of polystyrene products. As the particle size of TCP is reduced, there will be much better chance to engulf the styrene particles. The higher the number of TCP particles surrounding each styrene particle, the lesser will be their tendency to form a large particle after collision. Therefore, there will be higher percentages of spherical polystyrene with small particle size and narrower size distribution in the product. Experimental results have indicated that the addition of sodium hexametaPHOSPHATE (SHMP) to the reaction mixture of lime and phosphoric acid, after drying the product by spray dryer, lead to decrease the size of TCP particles from ca. 5 mm (without SHMP) to ca. 1.5 mm (with SHMP). In this study, the role of TCP containing SHMP as polymer suspension stabilizer and consequently the beads size of polystyrene is investigated in laboratory scale. The results show that despite addition of SHMP to the reaction mixture of lime and phosphoric acid decreases the TCP particles size and the mean bead size of the product of polystyrene become larger than the product prepared by TCP without SHMP.

Background: Some types of implants used for orbital implantation have side effects and complications. In this study we have evaluated beta-TRICALCIUM PHOSPHATE (b-TCP: ChronOS) granules as an orbital implant. Methods: Eighteen rabbits randomly allocated to four groups. Right eye enucleation performed in groups I to III followed by filling with autologous bone particles (n=5), a mixture of autologous bone particles and pure b-TCP granules (n=5), a mixture of autologous bone marrow and pure b-TCP granules (n=5). Right eye evisceration was done in group IV (n=3), and then filled with one of the aforementioned materials used in groups I, II and III. After 12 weeks, exenterated contents were compared by determining the volumes of the globes, area densitometry using dual-energy x-ray absorptiometry. Results: There was no significant difference between the volumes of enucleated globes before (groups I: 2.6±0.39, II: 2.6±0.12 and III: 2.5±0.3 (ml) and after surgery; (groups I: 2.5±0.4, II: 2.50±0.2 and III: 2.4±0.3). There was also no significant differences among the densities of exenterated contents of all groups; (I: 175±3, II: 165±1 and III: 174±3 mg/cm2). In all enucleated groups, histopathologic evaluations showed remarkable vascularization and fibrous ingrowth which were remarkable in eviscerated group. No significant complication was observed. Conclusion: b-TCP granules offer good cosmetic results with low risk of infection and extrusion. However, further studies are required before they can be used in human as a new orbital implant.

Alpha-TRICALCIUM PHOSPHATE can be used as a powder component in the preparation process of calcium PHOSPHATE cements in hard tissue applications. In this study, the mentioned powder was synthesized through chemical precipitation method using calcium nitrate and diammonium hydrogen PHOSPHATE as the raw materials. The resulting powder was heat-treated at 1250 °C and quenched at the ambient temperature. The results of X-Ray Diffraction (XRD) analysis and Fourier Transform Infrared (FTIR) spectroscopy confirmed the formation of crystalline Alpha-TRICALCIUM PHOSPHATE phase and presence of P-O chemical groups, respectively. The Single-component cement was prepared using Alpha-TRICALCIUM PHOSPHATE powder with the liquid phase containing 2.5 % disodium hydrogen PHOSPHATE. The resulting cement sample had an initial setting time of 17 1 minute and the compressive strength of 21 2 MPa. The XRD and FTIR experiments revealed the formation of a great amount of calcium deficient hydroxyapatite as the resulting cement product. According to the findings, the cement setting occurred through the hydrolysis of Alpha-TRICALCIUM PHOSPHATE powders and the formation of calcium deficient hydroxyapatite nanoflakes of approximately 500 nm in length. Finally, the cement acellular bioactivity experiment confirmed that the hydroxyapatite was formed on the outer surface of the cement during 14 days of immersion in the simulated body fluid.

Introduction: Calcium PHOSPHATE nanoparticles such as nano hydroxyapatite have shown excellent physical, chemical and biological properties and have allocated special place in regenerative medicine applications. Recently, the inhibitory effect of hydroxyapatite, as a calcium PHOSPHATE, on many cancers has been reported.Methods: In this article B-TRICALCIUM PHOSPHATE was synthesized using co-precipitation method and its physicochemical properties were studied (SEM, FTIR and XRD). Inhibitory effect of beta-TRICALCIUM PHOSPHATE nanoparticles on the growth and proliferation of breast cancer cell line MCF-7 was investigated.Results: In vitro MTT assay studies showed that the inhibitory effect was dependent on the concentration of TRICALCIUM PHOSPHATE nanoparticles. In addition, the results demonstrated that the inhibitory effect was 78% attributed to 50 mg. L-1 concentration of TRICALCIUM PHOSPHATE nanoparticles.Conclusion: In lowest concentrations, the inhibitory effect of TRICALCIUM PHOSPHATE nanoparticles was higher than others.

Background: After bone fractures from traffic trauma, many patients suffer from non-healing bone defects and its cosmetic and psychological complications. So, it is important to identify modern and effective methods to improve healing of bone defects. One of these is using bone cells from the patient, culturing these cells on appropriate scaffold, and finally transferring them to injured area.The main objective of this study was to compare the rate of osteoblast proliferation in alginate beads, and hydroxyapatite-TRICALCIUM PHOSPHATE (HA-TC) scaffold.Methods: Bone tissue specimens were obtained from 4 patients undergoing craniotomy surgery operations in Alzahra teaching hospital, Isfahan.Bone specimens were cut in to small pieces and put in Petri dishes having culture medium and transferred to the incubator. The mean interval of osteoblast outgrowth from bone pieces was observed to be 10-12 days, later on.The cell cultures reached confluence, averagely after 2 weeks time. First passage cells were detached from Petri dishes using Trypsin_ EDTA and were divided in two portions. One portion was used for hydroxyapatite-TRICALCIUM pohosphate scaffold, and the other was added to alginate gel. After a 2-weeks period, the data were collected and analyzed.Findings: The osteoblasts in hydroxyapatite-TRICALCIUM PHOSPHATE scaffold and alginate gel had round morphology. Van kossa staining demonstrated mineralized matrix in both groups.The number of harvested cells in 2 weeks after culture was significantly higher in Alginate group (P<0.001). In addition, MTT assay showed significant difference in the mean of viability rates between both groups in day 14 (P<0.001).Conclusion: This study showed that Alginate gel support better proliferation and viability of osteoblasts in comparison with the hydroxyapatite-TRICALCIUM pohosphate scaffold. The probable cause of these differences can be searched in Alginate bioproperties. Porosity of Alginate gel provides conditions in which cellular and methabolic activities could be accelerated

Background & Objectives: Many soil microorganisms are ale to solve unavailable phosphorus through metabolic activity and secretion of organic acids. This study was aimed to isolate TRICALCIUM PHOSPHATE active solubilizing bacteria from wheat and barley farms in Marvdasht Plain.Materials & Methods: This cross-sectional study was conducted on 50 barley and 50 wheat farms in Marvdasht Plain. The soil samples were enriched in NRIP media containing 10 percent TRICALCIUM PHOSPHATE. The TRICALCIUM PHOSPHATE solubilizing bacteria which produced halos on media were determined through biochemical tests, PCR and sequencing techniques. The activity of two active bacteria isolated from wheat and barley farms were analysed by HPLC method in order to investigate the production of secreted organic acids.Results: Overall 9 (18%) and 6 (12%) of the TRICALCIUM PHOSPHATE solubilizing bacteria were isolated from the wheat and barley farms located at Marvdasht, respectively. The HPLC analysis showed that the microorganisms isolated from barely and wheats farms produce 4 and 3 respectively, different low molecular weight acids.Conclusion: Since most of the TRICALCIUM PHOSPHATE active solubilizing bacteria were isolated from the barely farms, these bacteria can be found in the soils in which less Phosphorus fertilizers were used. Screening of these bacteria in different farms and their identification can be useful in the production of biologic fertilizers and growth of plants in that area.