POLYMER USES IN TISSUE ENGINEERING

The biodegradable polymer, poly(caprolactone) (PCL), was used to dip-coat silicon-stabilized resorbable calcium phosphate ceramic pellets and scaffolds implants. The PCL coatings increased in thickness on the dense ceramic pellets with the number of dipping and did not detach from the ceramic substrates during mechanical testing. The distribution of PCL in the porous scaffolds was not homogeneous, i.e. mostly located along the outer surface areas and at the interconnection of struts. The scaffolds with thick PCL coatings were handled in ways analogous to those that are used in clinical applications, such as drilling, screwing, cutting and grinding, etc.; it was found that this could be done without powdering or shattering. The compressive failure features of the thickly PCL-coated scaffolds were quite different from those of uncoated scaffolds and those with thin PCL coatings. For uncoated scaffolds or those with a thin PCL coating, the compressive strength decreased quickly from the yield point to zero after failure, but for the thick PCL-coated scaffolds, it became nearly constant strength after a quick decrease from the yield point, and started increasing towards the end of a constant strain region.