In Vitro Mineralization of Silicon Containing Calcium Phosphate Bioceramics

Abstract

In vitro mineralization of silicon containing calcium phosphate (Si‐CaP) bioceramics was investigated in the constant‐composition double‐diffusion (CCDD) device under physiological conditions. The experiments were performed with porous pellets made of Si‐CaP, which was synthesized from Ca(NO3)2·4H2O, NH4H2PO4, ammonia and fumed silica according to a newly developed single‐stage preparation route. Twice as condensed aqueous solutions of the Kokubo's revised simulated body fluid (rSBF) were used as mineralizing medium. All samples of Si‐CaP bioceramics possessed excellent in vitro mineralizing properties and, therefore, this material is ready for further trials with cells. Simultaneously, the workability of the CCDD device in a less condensed (twofold instead of the previously used fourfold) aqueous solutions of rSBF was confirmed.

Devitrification studies of wollastonite–tricalcium phosphate eutectic glass

“…In the last decade, intensive research has been devoted to preparing doped calcium phosphate materials to improve the osteogenesis, bioreabsorption rate, strength and phase composition of the resulting bioceramics. In particular, silicon [7][8][9][10][11][12][13][14][15][16] has received great attention as a constituent in phosphatebased bioceramics and glass-ceramics for biomedical applications. Silicon plays an essential role in the metabolic events conducive to endochondral and intramembranous bone formation [17][18] and, together with calcium, sodium and phosphorus (as released from 45S5 Bioglass), acts on the expression of certain genes responsible for controlling the cell cycle of animal and human osteoblasts and stimulates osteoproduction [19][20][21].…”

Structural and chemical analysis of silica-doped β-TCP ceramic coatings on surgical grade 316L SS for possible biomedical application

“…But it contributes a threat to the reduction in implant strength and its dissolution rate is altered by chemical modification. The crystallographic study of ␤-TCP revealed that the Ca (4) and Ca (5) are distinct from the other three sites and are ideal for substitution with smaller cations. Ca (4) having coordination number of 3 in the flattened tetrahedral configuration has an unusual coordination to O (9), O (9 ) and O (9 ) face of P (1) O 4 group resulting in compressed Ca site.…”

“…But ␤-TCP exhibits optimal level of solubility in biological fluid and the chemical composition is similar to apatite present in bone tissues. Hence, this material has extensively been used for bone grafting [5]. ␤-TCP is an attractive biomedical material owing to its excellent biocompatibility and the nontoxicity of its chemical components.…”

“…Ca (4)· · ·O (9) bond length is 3.041Å and longer than the normal Ca· · ·O bonds of length 2.4Å. Ca (5) sites are surrounded by O in sixfold distorted octahedral coordination, thus making small ionic substitution possible [8,9].…”

Modification of niobium surfaces using plasma electrolytic oxidation in silicate solutions

“…Increasing the Si content in the investigated CaP-SiO 2 bioceramics (up to 80 % by weight) resulted in higher concentrations of proteins and higher alkaline phosphatase specific activity. Dorozkhin [40] studied how the incorporation of silica into the CaP bioceramics affected the process of biomineralisation in revised simulated body fluid (r-SBF). The investigated composite was composed of 60-65 % silicon-stabilised alpha tricalcium phosphate (α-TCP), 30-35 % HA and balance Si, by weight.…”