The influence of different composite mixtures (PLA/HA) manufactured with additive laser technology on the ability of S. aureus and P. aeruginosa to form biofilms

Staphylococcus aureus (Gram-positive coccus) and Pseudomonas aeruginosa (Gram-negative bacterium) are the leading etiologic agents of biofilm-related, life-threatening infections in patients after orthopaedic implantations. The aim of the present paper is to estimate the ability of these two bacterial strains to form a biofilm on bioresorbable composites manufactured from polylactide (PLA) and hydroxyapatite (HA) with the use of Selective Laser Sintering (SLS) method. Methods: Microbiological tests were conducted on two variants of a solid specimen made with additive laser technology. Samples with different content of hydroxyapatite were made, with appropriate manufacturing parameters to ensure stability of both composite ingredients. The geometry of samples was obtained by technical computed tomography. Microbiological tests determined the number of bacterial cells after incubation. Results: The results indicate significantly decreased ability of S. aureus and P. aeruginosa to form biofilms on the surface of materials with higher content of hydroxyapatite ceramics. Conclusions: The data may be useful for future applications of SLS technology in the production of bioresorbable PLA/HA medical implants