Bone cements of calcium-magnesium phosphate and magnesium oxide

SUMMARYGrowing wether sheep in metabolism cages were fed a low phosphorus diet (0·75g P/day) supplemented with 1·75 g P/day as either a magnesium phosphate (20·0% Mg, 18·5% P) or a calcium magnesium phosphate (16·1% Ca, 6·0% Mg, 18·5% P). In addition, the magnesium phosphate provided 1·87 g Mg/day and the calcium magnesium phosphate 0·57 g Mg/day. In each case comparisons were made with equivalent amounts of phosphorus and magnesium supplied as dicalcium phosphate (26·5% Ca, 16·0% P) and magnesium oxide (60·0% Mg).All the supplements resulted in similar positive phosphorus retentions of between 0·77and 0·92 g P/day compared with a daily loss of 0·17 g P/day for the low phosphorus diet. Calcium retentions were higher (1·40 and 1·70 g Ca/day) whendicalcium phosphate rather than the magnesium phosphates (1·16 g Ca/day) were given. Magnesium retentions were increased from 0·1 g Mg/day (unsupplemented) to 0·3–0·4 gMg/day and were similar for both magnesium oxide and the magnesium phosphates.Blood phosphorus and magnesium concentrations were increased to a similar degree by all forms of supplementation.

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Effects of mesoporous calcium magnesium silicate on setting time, compressive strength, apatite formation, degradability and cell behavior to magnesium phosphate based bone cements

RSC Advances ◽

10.1039/c6ra25503e ◽

2017 ◽

Vol 7 (2) ◽

pp. 870-879 ◽

Cited By ~ 6

Author(s):

Liehu Cao ◽

Weizong Weng ◽

Xiao Chen ◽

Jun Zhang ◽

Qirong Zhou ◽

...

Keyword(s):

Compressive Strength ◽

Setting Time ◽

Magnesium Silicate ◽

Magnesium Phosphate ◽

Cell Behavior ◽

Bone Cements ◽

Apatite Formation ◽

Calcium Magnesium ◽

Composite Cements

Mesoporous calcium magnesium silicate was doped into magnesium phosphate to fabricate magnesium phosphate based composite cements (MBC).

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In-Vivo Degradation Behavior and Osseointegration of 3D Powder-Printed Calcium Magnesium Phosphate Cement Scaffolds

Materials ◽

10.3390/ma14040946 ◽

2021 ◽

Vol 14 (4) ◽

pp. 946

Author(s):

Katharina Kowalewicz ◽

Elke Vorndran ◽

Franziska Feichtner ◽

Anja-Christina Waselau ◽

Manuel Brueckner ◽

...

Keyword(s):

Three Dimensional ◽

Bone Substitutes ◽

Magnesium Phosphate ◽

Degradation Behavior ◽

Micro Computed Tomography ◽

Calcium Magnesium ◽

Interest In Research ◽

In Vivo Degradation ◽

Volume Decrease

Calcium magnesium phosphate cements (CMPCs) are promising bone substitutes and experience great interest in research. Therefore, in-vivo degradation behavior, osseointegration and biocompatibility of three-dimensional (3D) powder-printed CMPC scaffolds were investigated in the present study. The materials Mg225 (Ca0.75Mg2.25(PO4)2) and Mg225d (Mg225 treated with diammonium hydrogen phosphate (DAHP)) were implanted as cylindrical scaffolds (h = 5 mm, Ø = 3.8 mm) in both lateral femoral condyles in rabbits and compared with tricalcium phosphate (TCP). Treatment with DAHP results in the precipitation of struvite, thus reducing pore size and overall porosity and increasing pressure stability. Over 6 weeks, the scaffolds were evaluated clinically, radiologically, with Micro-Computed Tomography (µCT) and histological examinations. All scaffolds showed excellent biocompatibility. X-ray and in-vivo µCT examinations showed a volume decrease and increasing osseointegration over time. Structure loss and volume decrease were most evident in Mg225. Histologically, all scaffolds degraded centripetally and were completely traversed by new bone, in which the remaining scaffold material was embedded. While after 6 weeks, Mg225d and TCP were still visible as a network, only individual particles of Mg225 were present. Based on these results, Mg225 and Mg225d appear to be promising bone substitutes for various loading situations that should be investigated further.

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