[Initial colonization of composite resins by Streptococcus mutans: the influence of polishing]

The purpose of the present investigation was to compare the in vitro initial colonization of Streptococcus mutans on three composite materials (HERCULITE, FILLISPAD and SILIFILL) regarding the polishing procedure (SOFT-LEX, 3M). Surface roughness and bacterial deposit were analyzed by SEM and the deposit was estimated using a modified method of SKJORLAND. Results indicated that surface roughness was reduced by the polishing procedure, but this roughness was more important at the periphery of restorations. Bacterial deposit was strongly reduced on the polished materials but bacteria not adhered in the same number on the composites with a comparable surface roughness: the accumulation of bacteria was less important on FILLISPAD materials. It is concluded that the initial colonization of resin composites was not only dependent of surface roughness.