Biodegradable material components

Abstract

A biodegradable material for use in making items usable in surgery and related fields of medicine. The material comprising a bioabsorbable thermoplastic polymer component and a bioactive filler material. In components made of the material particles of the filler material occur embedded within the surface of the components.

1 . A component made of a biodegradable material which material comprises a bioabsorbable polymer component and a bioactive filler material characterised in that particles of the filler occur embedded within the surface of the component.  
     
     
         2 . A component according to  claim 1  characterised in that, the component comprises any of a screw, pin, plate, suture, wound care patch, spinal spacer, osteotomy wedge, cement restrictor, non-woven mesh or other item usable in surgery and related fields of medicine.  
     
     
         3 . A method of making a biodegradable material usable to make a component according to  claim 1 , characterised in that the method comprises mixing together a bioabsorbable polymer component and a bioactive filler material.  
     
     
         4 . A method according to  claim 3  characterised in that, the polymer component and filler are mixed together in the form of granules each having similar particle size ranges.  
     
     
         5 . A method according to  claim 3  characterised in that, the particle size is between 0.5 mm and 5 mm.  
     
     
         6 . A method according to  claim 3  characterised in that, the polymer component and filler are mixed together in the form of dry particulate materials.  
     
     
         7 . A method according to  claim 3  characterised in that, the polymer component is coated with the filler.  
     
     
         8 . A method according to  claim 3  characterised in that, the polymer component is wetted with a solvent prior to or during mixing.  
     
     
         9 . A method according to  claim 8  characterised in that, the solvent comprises chloroform.  
     
     
         10 . A method according to  claim 8  characterised in that, the polymer component is sprayed onto the filler.  
     
     
         11 . A method according to the  claim 8  characterised in that, the material is subsequently dried to remove the solvent.  
     
     
         12 . A method according to  claim 3  characterised in that, the particle size of the polymer component is reduced prior to mixing with the filler.  
     
     
         13 . A method according to  claim 12  characterised in that, the polymer component is milled.  
     
     
         14 . A method according to  claim 13  characterised in that, the polymer component is cryogenically milled.  
     
     
         15 . A method according to  claim 3  characterised in that, the particle size of the filler is increased prior to mixing with the polymer component.  
     
     
         16 . A method according to  claim 15  characterised in that, the filler material is caused to agglomerate or granulate.  
     
     
         17 . A biodegradable material, characterised in that, the material is formed by a method according to  claim 3 .  
     
     
         18 . A material according to  claim 17  characterised in that, the mixture is substantially homogenous.  
     
     
         19 . A material according to  claim 17  characterised in that, the polymer component is synthetic.  
     
     
         20 . A material according to  claim 17  characterised in that, the polymer component comprises a polyester.  
     
     
         21 . A material according to  claim 17  characterised in that, the polymer component comprises one or more polymers or co-polymers of lactic acid (L and/or D), glycolic acid, hydroxybutyric acid, hydroxyvaleric acid, poly dioxanone, poly caprolactone, poly ethylene oxide or poly butylene terephthalate.  
     
     
         22 . A material according to  claim 17  characterised in that, the filler comprises alone or in combination, a calcium phosphate, calcium sulphate or carbonate bioceramic filler, or a bioactive glass.  
     
     
         23 . A material according to  claim 22  characterised in that, the filler comprises hydroxyapatite and/or beta tri-calcium phosphate.  
     
     
         24 . A material according to  claim 17  characterised in that, the filler has a particle size of substantially less than 100 microns.  
     
     
         25 . A material according to  claim 17  characterised in that the filler constitutes between 1% and 50% of the mixture by weight.  
     
     
         26 . A material according to  claim 25  characterised in that, the filler constitutes between 15% and 35% of the mixture by weight.  
     
     
         27 . A material according to  claim 17  characterised in that, the filler additionally comprises, alone or in combination, a sacrificial porosifier.  
     
     
         28 . A material according to  claim 27  characterised in that, the sacrificial porosifier comprises a water soluble, heat stable inorganic salt.  
     
     
         29 . A material according to  claim 28  characterised in that, the inorganic salt comprises sodium chloride.  
     
     
         30 . A material according to  claim 29  characterised in that, the sodium chloride is in the form of a finely divided powder.  
     
     
         31 . A material according to  claim 29  characterised in that, the sodium chloride constitutes between 1% and 50% by weight of the material.  
     
     
         32 . A material according to  claim 17  characterised in that, the material substantially comprises no mechanically free filler particles with a diameter less than 100 microns.  
     
     
         33 . A method of making a component according to  claim 1 , characterised in that, the method comprises moulding a material according to  claim 17 .  
     
     
         34 . A method according to  claim 33  characterised in that, the moulding is in the form of a selected one of injection moulding, compression moulding, extrusion, extrusion followed by a selected melt forming technique.  
     
     
         35 . A method according to  claim 33  characterised in that, the material is fed to a moulding machine, with at least a substantial proportion of the material in the form of granules with a diameter of between 0.5 and 5 mm.  
     
     
         36 . A method according to  claim 33  characterised in that, the material is dried prior to moulding.  
     
     
         37 . A method according to  claim 33  characterised in that, the component is annealed subsequent to moulding.