| US 7,547,448 B2 | ||
| Bone replacement material comprising crystalline and X-ray amorphous phases | ||
| Georg Berger, Zepernick (Germany); Andrea Spitzer, Berlin (Germany); Christian Jäger, Berlin (Germany); Jutta Pauli, Berlin (Germany); and Renate Gildenhaar, Berlin (Germany) | ||
| Assigned to Bam Bundesanstalt fuer Material Forschung und Pruefung, Berlin (Germany) | ||
| Filed on Oct. 20, 2003, as Appl. No. 10/689,219. | ||
| Claims priority of application No. 102 49 627 (DE), filed on Oct. 21, 2002. | ||
| Prior Publication US 2004/0228927 A1, Nov. 18, 2004 | ||
| This patent is subject to a terminal disclaimer. | ||
| Int. Cl. A61F 2/28 (2006.01) | ||
| U.S. Cl. 424—426 | 16 Claims |
| 1. A bone replacement material comprising crystalline and X-ray amorphous phases, characterized in that
a) according to 31P-NMR measurements, the bone replacement material comprises Q0-groups of orthophosphate and Q1-groups of diphosphate, the orthophosphates or Q0-groups making up 70 to 99.9% by weight relative to the total phosphorus content of the finished material and the diphosphates
or Q1-groups making up 0.1 to 30% by weight relative to the total phosphorus content of the finished material, and
b) according to X-ray diffractometric measurements and relative to the total weight of the finished material, 30 to 99.9%
by weight of a main crystal phase consisting of Ca2K1−xNa1+x(PO4)2, where x=0.1 to 0.9, is contained in the bone replacement material and 0.1 to 20% by weight of a substance selected from
the group consisting of Na2CaP2O7, K2CaP2O7, Ca2P2O7 and the mixtures thereof is contained as a secondary crystal phase, and
c) the X-ray amorphous phases contained besides the main crystal phase jointly make up 0.1 to 70% by weight relative to the
total weight of the finished material,
obtainable by
mixing raw materials containing (in % by weight) 28-33 CaO, 8.5-13 Na2O, 9.5-15 K2O, 1.5-3 MgO and 0.1-4 SiO2 and treating the aforesaid mixture with H3PO4 in an amount corresponding to 40-52 P2O5, SiO2 or MgO or a mixture thereof making up at least 1% by weight, homogenizing and drying the mixture and subjecting it to a step-by-step
thermal treatment lasting 1-2 h at 350-450° C., 750-850° C. and 950-1,050° C. respectively, melting the mixture at between
1,550 and 1,650° C., holding it at the melting temperature for between 10 and 60 minutes and finally cooling the mixture in
a spontaneous or temperature-controlled manner, grinding it, if necessary, and sintering it to obtain moulded bodies.
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