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.

Background: The aim of this study was to make a bioactive bone CEMENT based on poly (methyl methacrylate) (PMMA) with suitable mechanical properties. Methods: PMMA has been modified by fabricating a composite consisting of biphasic CALCIUM PHOSPHATE (BCP) 68 wt%, PMMA 31 wt% and graphene (Gr) 1 wt% (PMMA/BCP/Gr), 32 wt% of PMMA, and 68 wt% of BCP (PMMA/BCP) and pure PMMA by milling, mixing with monomer liquid, and casting. The modified CEMENTs were evaluated regarding mechanical properties, bioactivity, degradation rate, and biocompatibility. Results: The scanning electron microscopy (SEM) images of hydroxyapatite (HA) formed on samples surface after 28 days of immersion in simulated body fluid (SBF) demonstrated that bioactivity was obtained due to the addition of BCP, and the degradation rate of the CEMENT was enhanced as well. Investigations of mechanical properties revealed that BCP increased the elastic modulus of PMMA more than 1. 5 times, but predictably decreased elongation. The addition of 1 wt% Gr increased elongation and yield strength from 16. 39% ± 1. 02% and 61. 67 ± 1. 52 Mpa for PMMA/BCP to 35. 18% ± 2. 42% and 78. 40 ± 2. 06 Mpa for PMMA/BCP/Gr, respectively. MG63 cells survival and proliferation improved from 127. 55% ± 7. 03% for PMMA to 201. 41% ± 10. 7% for PMMA/BCP/Gr on Day 4 of culture. Conclusion: According to the obtained results of mechanical and biological tests, it seems that new PMMA/BCP/Gr bone CEMENT has a potentiality for usage in orthopedic applications.

Introduction: Root mineral trioxide aggregate (MTA) is a type of MTA that has been introduced in the Iranian market. There have been few studies on this substance. This study compared the push-out bond strength of Root MTA and CEM CEMENT, which were both Iranian products. Materials & Methods: This in vitro study was performed on 20 extracted maxillary incisors. Samples were divided in two groups. The canals of the first group were filled with Root MTA and the second group by CEM CEMENT. In order to investigate the push-out bond strength, the device applied a force in the direction parallel to the longitudinal axis of the sample so that the desired materials would fail. Each sample was classified into one of three types of failureincluding adhesive (failure in the material and dentin interface), cohesive (failure in the material itself) or a combination of both. Results: There was no significant difference between the mean pressure on teeth for the two groups (P>0. 05). There was no significant difference between the frequencies of different types of failure between the two groups (P>0. 05). Cohesive failure in the CEM group was twice as high as in the MTA group (P>0. 05). Conclusion: There was not any significant difference between the push-out bond strength of CEM CEMENT and Root MTA CEMENT. These findings demonstrated that Root MTA material showed a satisfactory result in the bond strength test compared to CEM material, and could be used as an alternative to CEM CEMENT.

CALCIUM PHOSPHATE CEMENTs are widely used in repairing bone and dental defects recently. These CEMENTs exhibit excellent biocompatibility and osteoconductivity. In this research, CALCIUM PHOSPHATE CEMENTs are prepared with the ratio of 1/p=OA by mixing powder components consists of Na2SO4, b-TCP, MCPM and liquid component Na2HPO4 (4 weight percent concentration). The initial setting time was equal to 7 minutes and the final setting time is 20 minutes. The compressive strength of samples is measured in different times of incubation. Then, the gentamycine sulfate drug is added to liquid component with concentration of 80mg/2ml in ratio of 1/6. The results imply that the initial and final setting time of samples are decreased to 5 and 15 minutes, respectively due to the presence of sulfate ion in the drug. However, compressive strength of samples increased after drug addition. Microstructure of the fracture surface is studied with scanning electron microscope (SEM). The amount of the drug released in ringer solution is measured within different incubation times. The analysis revealed the fact that the amount of the drug release reached its maximum value in 15th day that is 35% of its primary value.