Sintered composite material, a process of making same, and a method of using same

Claim 1

A process for the production of a composite therapeutically useful as a prosthetic material for replacing bones and teeth of humans and animals, said process comprising the steps of: (a) comminuting a mixture of about 20 parts fluorapatite Ca 5 [F(PO 4 ) 3 ] prepared by precipitation and about 34 parts glass composition consisting essentially in weight percent of: between about 20% and about 60% of silicon oxide, SiO 2 , between about 5% and about 40% of phosphorus pentoxide, P 2 O 5 , between about 2.7% and about 20% of sodium oxide, Na 2 O, between about 0.4% and about 20% of potassium oxide, K 2 O, between about 2.9% and about 30% of magnesium oxide, MgO, and between about 5% and 40% of calcium oxide, CaO, (b) classifying the ground mixture by means of a screen into two fractions of different particle size; (c) finely comminuting the fraction of smaller particle size to about 30 μm; (d) compressing and molding the finely comminuted mixture into a shaped body at a pressure of about 300 atmospheres while simultaneously subjecting the mixture to a heat treatment of about 100° C for a period of about 20 minutes; and (e) sintering the compressed and molded shaped body at atmospheric pressure and at a temperature of about 670° C for a period of time of about 100 minutes whereby said glass composition is melted and said composite produced is characterized by discrete crystallites of said fluorapatite dispersed in a matrix of said glass.