Method of making a medical prosthesis

Claim 1

Method to make a bone replacement prosthetic structure or appliance of a biologically compatible material suitable as a bone replacement prosthetic implant including a core element made of a fiber-reinformed thermosetting material; and a surface element made of a biologically compatible fiber reinforced thermoplastic material completely surrounding said core element and internally interlocked with the core element comprising steps of providing an inner support structure of at least one material selected from the group consisting of: elongated essentially parallel positioned fibers, woven fiber fabric, fiber mats, matted fibers and felted fibers; soaking the support structure in a thermo-setting resin; surrounding said soaked inner support structure with a surface structure comprising a biologically compatible thermoplastic resin, at least a portion of the thermoplastic resin being at the side remote from the thermosetting resin soaked support structure to form a sub-assembly, said thermosetting resin being a resin that will cure at a temperature which overlaps in the temperature range of from 160° C. to 200° C. with the temperature range of softening of said thermoplastic resin; introducing said sub-assembly into a mold having the desired shape of the prosthetic structure or appliance; simultaneously heating to a temperature of from 160° C. to 200° C. at which said thermosetting resin cures and said thermoplastic resin softens and compressing the mold to compress the sub-assembly and cure the thermosetting resin and thereby form said core element and mold the thermoplastic resin and thereby causing the outer thermoplastic structure to interlock with the inner support structure and forming the surface structure with an outer surface consisting essentially only of thermoplastic resin; and removing the mold after cooling to a temperature at which the outer surface of the thermoplastic resin has solidified.