Fig 3. Production of biofilm on polystyrene, collagen I and collagen IV coated surfaces.

Isolates were classified as non-biofilm producers (OD₆₀₀<0.120), weak producers (0.120<OD₆₀₀≤0.240) and strong producers (OD₆₀₀>0.240). Results are expressed as mean values (± SD). Biofilm production among the enterococcal and the streptococcal groups was compared using Mann Whitney U-test.