Evaluation of a biofilm formation by Desulfovibrio fairfieldensis on titanium implants
Abstract
The aim of this study was to assess the capabilities of Desulfovibrio fairfieldensis to colonize the grade 4 titanium coupons (modSLA) used in dental implants. The effect of ampicillin, which is known to be a poorly penetrating agent in the matrix biofilm, was also compared with planktonic and sessile cells. The modSLA colonization by bacteria in KNO3 (005moll(-1)) and culture media (DSM 63 and fetal bovine serum) was determined by direct cell counts and field emission electronic microscopy. The surface of titanium (Ti) coupons was characterized by scanning electron microscopy and by Raman spectroscopy. Cells, mainly located in surface pores of modSLA coupons, appeared to be wrapped in a polymeric-like structure. The initial apparent rates of adhesion varied from 3x10(6) to 30x10(6)cellscm(-2)h(-1), and a plateau was reached at 1day, regardless of the incubation medium. No cells have significantly adhered to polished Ti, and a minority was found on massive Ti. Finally, cells trapped on the modSLA surface were not lysed by ampicillin contrary to planktonic cells. Des. fairfieldensis is therefore able to colonize the rough surface of modSLA implant through a physical trapping in the microporosity of the surface, where they can produce a biofilm-like structure to improve their resistance to ampicillin.