In vivo analysis of bacterial biofilm formation on facial plastic bioimplants

Objectives: This study examines the formation of biofilm on biomaterials commonly used in facial plastics and reconstruction including titanium, silicone, ion-bombarded silicone (Ultrasil), e-PTFE (Gore-Tex), and PHDPE (Medpor). Methods: These biomaterials were implanted subcutaneously in the dorsum of 11 guinea pigs after contamination with Staphylococcus aureus and examined with scanning electron microscopy after 7 days. Wounds were also inspected for infection and extrusion rates. Results: Results show biofilm formation on titanium, silicone, ion-bombarded silicone, e-PTFE, and PHDPE associated with high rates of extrusion and infection. Implants of e-PTFE with silver/chlorhexidine, on the other hand, appeared resistant to biofilm formation and demonstrated significantly lower rates of extrusion and infection. Conclusions: contamination of bioimplants in vivo leads to formation of bacterial biofilm on the surface of the biomaterial, causing infection, pus formation, and extrusion. The authors hypothesize that the antiseptic agents impregnated in the biomaterial form a protective coat of silver, chlorhexidine, and inflammatory cells that inhibits initial bacterial adhesion to the biomaterial surface.