Low-Temperature Magnesium Calcium Phosphate Ceramics with Adjustable Resorption Rate

Abstract

Low-temperature ceramics based on magnesium calcium phosphate cement are a promising resorbable material for bone tissue restoration with the possibility of functionalization. The replacement of the magnesium Mg2+ ion with a calcium Ca2+ ion at the stage of preparation of the precursor leads to the production of multiphase ceramics containing phases of brushite, monetite, and newberyite, with different dissolution rates. Multiphase ceramics leads to volumetric resorption with preservation of their geometric shape, which was confirmed by the results of an evaluation of the output of magnesium Mg2+ and calcium Ca2+ ions into the contact solution of the ceramics and the X-ray density of ceramic samples during subcutaneous implantation. The combined introduction of sodium pyrophosphate decahydrate and citric acid monohydrate as setting inhibitors neutralizes their insignificant negative effect on the physico-chemical properties of ceramics (strength, pH, porosity), determining the optimal composition. In vivo experiments with setting inhibitors in the composition of ceramics showed a different biological response, affecting the rate of resorption on par with magnesium ions. Preliminary data on biocompatibility and solubility determined magnesium-calcium phosphate ceramics containing additives that regulate setting to be a potential material for bone tissue restoration and a vector for further research, including in orthotopic implantation models.

Viricidal Activity of Thermoplastic Polyurethane Materials with Silver Nanoparticles

“…In these regards, there are several conditioning factors such as, mainly, the ability of each element to be released from the source material and their solubility in water. In comparison to other studies, similar delivery trends associated with the degradation of ceramic components have already been described [38,39]. In quantitative terms for each particular element, the release rate of Ag and Al ions was approximately 4 ppm/h for each one, while that of Mg was about six times higher (28.4 ± 5.7 ppm/h).…”

Calcium Phosphate Loaded Biopolymer Composites—A Comprehensive Review on the Most Recent Progress and Promising Trends

“…The quality of calcium precursors used also affects the morphology, and the particle size and shape [22]. Other methods applied for CaP preparation include hydrothermal [23][24][25], sol-gel [26,27], electrochemical [28], solid phase powder milling [29][30][31], and spray freeze-drying techniques [32,33]. Additionally, because the human bone contains trace elements such as Mg, Zn, Sr, etc., the mineralization of CaP particles with such bioactive ions makes them more biocompatible.…”

Calcium Phosphate Cements as Carriers of Functional Substances for the Treatment of Bone Tissue

“…Figure 6 shows the process of bone defect replacement during the implantation of calcium phosphate material in the form of a block, granules or cement paste. Currently, calcium phosphate materials are used in the field of traumatology and orthopedics in the form of powders, granules, blocks, cements and coatings on metal implants [117][118][119][120][121][122]. Due to the high strength of ionic bonds, calcium phosphate materials are brittle and cannot carry heavy loads.…”

“…As a result of the acid-base reaction, cements based on hydroxyapatite Ca 10 (PO 4 ) 6 (OH) 2 (HA) (Ca/P = 1.67)/calcium-deficient hydroxyapatite Ca 10−x (HPO 4 ) y (PO 4 ) 1−y ) 6 (OH) 2 (CDHA) (Ca/P = 1.5) and brushite CaHPO 4 •2H 2 O (DCPD) (Ca/P = 1)/monetite (dicalcium phosphate anhydrite) CaHPO 4 (DCPA) (Ca/P = 1) are obtained by reacting tetracalcium phosphate Ca 4 (PO 4 ) 2 O (TTCP) (Ca/P = 2) or β-tricalcium phosphate β-Ca 3 (PO 4 ) 2 (β-TCP) (Ca/P = 1.5) with DCPD (Ca/P = 1)/DCPA or monocalcium phosphate monohydrate Ca(H 2 PO 4 ) 2 •H 2 O (MCPM) (Ca/P = 0.5), without the formation of acidic or basic co-products. Monetite is formed under conditions of water deficiency and low pH [120,140].…”

“…There are two approaches to ionic substitution: introducing additional compounds into the composition of the powder part of cement [195,196], or by doping one of the original components [120,170,194,197].…”