To investigate the microbial adherence and colonization of a polyspecies biofilm
on 7 differently processed titanium surfaces.
Material and Methods:
Six-species biofilms were formed anaerobically on 5-mm-diameter sterilized,
saliva-preconditioned titanium discs. Material surfaces used were either machined,
stained, acid-etched or sandblasted/acid-etched (SLA). Samples of the latter two
materials were also provided in a chemically modified form, with increased
wettability characteristics. Surface roughness and contact angles of all materials
were determined. The discs were then incubated anaerobically for up to 16.5 h.
Initial microbial adherence was evaluated after 20 min incubation and further
colonization after 2, 4, 8, and 16.5 h using non-selective and selective culture
techniques. Results at different time points were compared using ANOVA and Scheffé
post hoc analysis.
The mean differences in microorganisms colonizing after the first 20 min were in a
very narrow range (4.5 to 4.8 log CFU). At up to 16.5 h, the modified SLA surface
exhibited the highest values for colonization (6.9±0.2 log CFU, p<0.05) but
increasing growth was observed on all test surfaces over time. Discrepancies among
bacterial strains on the differently crafted titanium surfaces were very similar
to those described for total log CFU. F. nucleatum was below the
detection limit on all surfaces after 4 h.
Within the limitations of this in vitro study, surface roughness
had a moderate influence on biofilm formation, while wettability did not seem to
influence biofilm formation under the experimental conditions described. The
modified SLA surface showed the highest trend for bacterial colonization.