Production, by co-grinding in a media mill, of porous biodegradable polylactic acid–apatite composite materials for bone tissue engineering

This paper presents the results of a study of the production of porous biodegradable composite materials by co-grinding, followed by scaffolding. Dry powders of polylactic acid and nanocrystalline carbonated apatite, analogous to bone mineral were co-ground in a tumbling ball mill in order to disperse the mineral filler within the polymer. Porous scaffolds were then made by hot moulding the mixture of the two components along with a pore-forming agent which was subsequently eliminated by washing. The mechanical resistance of the scaffolds was evaluated in order to determine the best operating conditions to produce implants offering optimised properties for use as bone substitutes. It was shown that 30 wt.% of filler and 70 wt.% of pore-forming agent produce scaffolds which are sufficiently porous and resistant. Porous biodegradable polylactic acid-apatite composite scaffolds were produced combining co-grinding and hot moulding processes. A pore-forming agent was used during the moulding step and then eliminated by washing. It was shown that 30 wt. % of apatite and 70 wt. % of pore-forming agent permit to produce implants offering good interconnected macroporosity and mechanical properties for use as scaffold for bone tissue engineering. [Display omitted]